G'day moweasy,
Sounds like your getting stuck into this old bird!
Please forgive me if the following reply is 'talking down' to your engineering ability as I'm not sure what your level of machine savvy is.
Yes, the drive pulley bearings can be easily replaced and are 'dime a dozen' at your local bearing shop. When driving the bearings in or out please make sure the pulley is supported at the bearing outer diameter and not at the pulley edge. The thing is only aluminium and could very likely crack If not properly supported. You'll notice the bearings are staked to help retain them. When you go to remove the bearings there will be some initial resistance while you 'overcome' the staking. Keep the bearing square when driving in or out. Warming the pulley with a hot air gun (not a flame) is also a good idea.
I'm using loctite 641 when installing bearings. It offers adhesion but allows future removal without the anguish that might come with using a stronger grade. If the interference between the pulley and bearing is good, there is no need to use any product at all. It just a personal preference thing on my part. Once the new bearing is in restake the pulley at the bearing with a punch.
Another option is to take the pulleys to an engineering works with a press etc who can do it for you. The place that did the rework on the front axle for you could do this perhaps?
All the above applies equally to the wheel bearings.
On the subject of the rest of the clutch, I can see what looks like good cork on the left pressure plate in the photo. The cork starts out about 1/8" thick and is good to wear down to 1/16". The plate in the photo might be getting down towards the 1/16". The folks at the ODK shop can definitely help with the new corks. New corks are glued on with a good quality contact adhesive after first removing the old and thoroughly cleaning the plate with acetone and scotchbrite. Apply thinly to both surfaces and sit on a flat surface and weight down overnight.
The reason for the lack of 'spring back' from the pressure plates could be the springs but it could be that it's just sticking due to some sort of friction between the shaft and the pressure plates. This could be a burr or the like on the shaft or gunk or.....you'll know once it's apart. The plates must be 100 percent free on the shaft. Use a silicone spray lube on the shaft when it goes back together.
You'll notice shim washers under the springs.you need at least one on each side and only need more if there is not enough clearance between the pulleys and the pressure plates once it's been reassembled. The pulleys MUST be free to turn without binding on the pressure plates!
Phew! Sorry for the lengthy reply! I hope it's of some help.
Cheers,
