From the PWA7C Newsletter 1989 with many thanks

It is necessary to remove the power unit and the gearbox together from the chassis before they are separated to give access to the clutch.
Work inside the car first - remove the seat squabs and floor mats and the cover of the centre channel over the handbrake gear so that the fixing of the brake ratchet (1 bolt) to the gearbox can be removed. Access is also then afforded to the front fabric universal coupling, to disconnect it from the propellor shaft. The prop shaft spider should be eased back off the universal joint bolt, to avoid pulling out the rear universal joint blocks.
Remove the gearbox top cover with the change speed lever and sate, and place a temporary cover over the studs to prevent the intrusion of dirt or small parts while the repair is in progress. Undo the two nuts holding the accelerator control spindle bearings to the dash, disconnect the starter motor and battery, and remove the starter motor with its casing (lift it vertically off the positioning dowel.) This leaves everything clear inside the car.
Working outside, disconnect the dynamo leads (at the dynamo-note the correct terminals for when re-assembling), ignition leads and control, carburettor controls, fuel pipe (from float chamber union) oil pressure pipe (from its crankcase union) and the windscreen wiper tubing from the induction manifold.

Turning to the cooling system, it is first necessary to remove the starting handle (retained by a set screw). Drain off the cooling water, disconnect the top hose connections at the radiator, and the bottom hose connection at the cylinder block. The radiator can then be lifted clear when the three bolts holding it on each side to front of the body and the screw holding the tie rod have been removed. This gives access for removal of the starting handle bracket and packing (if any) which bolts to the front member of the frame.

Remove the exhaust pipe-to-manifold joint bolts, the induction manifold with carburettor, and the accelerator control spindle with the levers that it carries. Next remove the four engine bolts. The front offside bolt is under the magneto coupling; draw a line across the coupling under the magneto strap, and take off the magneto to give access to the bolt.

Before the engine can be pulled clear of the frame, it is necessary to remove the clutch pedal lever from its spindle. This is the most difficult operation in removing the engine. The position of the pedal lever fixing is immediately behind the steering gear (from the side of the car.) The engine has, therefore, to be pulled forward about three inches, before the lever and spindle are clear of the steering box. The lever is held on the spindle by a bicycle type cotter and the engine must be tilted over towards the nearside to lift the cotter and nut above the frame. Then remove the nut, drive out the cotter, and prise the lever off the spindle taking care not to lose the spring behind it. Lift the front of the engine, and pull the whole unit clear of the chassis, mount it on an engine stand and separate the gearbox from the engine.

Removal of the six set screws in the flywheel cover allows the cover with the declutching levers, the pressure plate, and the springs to be removed, giving access to the flywheel. Lock the flywheel from turning by a bar inserted in one of the holes in the rim, remove the flywheel nut and pull the flywheel off its keyed taper with a flywheel puller. To dismantle the pressure plate from the flywheel cover, just pull them apart, guiding the declutching levers through the holes in the cover. Take care not to lose the springs.
Remove the old linings from the flywheel, and the pressure plate, and rivet on the new.

The linings require careful rivetting or they may be cracked, and the rivet heads on the back of the flywheel should not stand up or they may foul the camshaft bearing. When re-lining the pressure plate, the withdrawal pins should be in place, as the lining holds them in their sockets.
It is as well, before reassembling, to examine the clutch withdrawal collar, left on the front cover of the gearbox, as clutch operation depends to a great degree upon the condition of this collar. Examine the points for wear where the declutching levers bear (uneven wear at these points will cause uneven clutch action - and if uneven wear is much apparent it is advisable to fit a new bearing pressure plate BJ.19) also whether the withdrawal levers engage (both should engage evenly) and for movement of the withdrawal collar on the gearbox front cover, which should be easy, without any binding. Another point which should be examined for wear is the bearing in the withdrawal collar.

Reassembly is largely a reversal of the dismantling operation, hut there are one or two points which deserve notice.

After re-assembling the pressure plate and the flywheel cover together, with the springs between them, re-fix them to the flywheel with the six set screws, the clutch plate being in the flywheel, in the same position as before removal, so that the timing marks coincide. Before tightening the set screws, centre the clutch plate so that the gearbox will fit up to it. When the six set screws have been tightened, and locked with the locking washers, test the distance of the end bearing faces of the declutching levers from the clutch plate face when they are about to act against the clutch springs. This distance should be one inch to one-and-three-sixteenths of an inch - each lever being the same distance from the clutch plate face. If the levers require re-setting, adjust them by bending with a slotted bar.

After refitting the gearbox to the engine, ensure that the clutch plate is free, when the clutch is out, by turning the flywheel with a bar in one of the holes in the rim, when the first motion shaft should remain still. If the first motion shaft (and therefore the clutch plate) moves, the clutch cannot be fully disengaged. Such a condition would be due to bad adjustment of the declutching levers, which should be re-adjusted so that the clutch can be freed entirely.

In replacing the engine in the chassis, rest the accelerator control spindle with levers, just at the back of the cylinder block, so that it will be in position for fitting to the dash. Replace the clutch pedal lever on its spindle with the engine in the same position as when it was removed. It is advisable to replace the spring on the spindle with its end in the small hole in the gearbox, before the engine is placed in the chassis.
When refitting the starting handle bracket, before tightening the bolts, line it up with the starting nut by means of the starting handle.
In refitting the radiator, the cowl bolts should be inside the front end of the body, not outside. On models which are not fitted with a radiator tie-rod, set the radiator in the right position by fitting the bonnet, before tightening three bolts on each side.