Hi Stew,
Well no thrust pad takes out about 5 mm of throw length and thus your clutch was never disengaging. I can't understand why it's not there. I reckon that when the previous tenant of the machine did the engine swap that they forgot it and thought bugger it I'm not going to pull it all apart again. Your original one was a brass unit but they've since been replaced with a black plastic replacement. You'll have to buy yourself one and install it on assembly, they're not expensive.
As far as the spring cork and bearing are concerned you'll find nothing wrong with the spring at all, the cork only needs to have around 1.5mm to 2mm of thickness on it to be OK and the bearing I would submerge in petrol to wash out while spinning it, then dry it out thoroughly and then submerge in oil for about 5 minutes. Pull it out and try to work out all the excessive oil as you don't want spare oil being flicked out inside the clutch housing as that will work against you.
Those cast iron clutch housings are like GOLD and you want to move heaven and earth not to have to move away from them and go to a die cast unit if you can help it.
I must admit that I would've thought that the bed knife could've gone another round after re-grinding but it does look rather thin on one end.
I'm glad that I've been able to help you with this one, but that's what this forum is all about.
Cheers,
BB.
