[jimTN]

You will need to lube the vac piston on the rear end. After setting all that time I would guess it is dried out and maybe flat on one side. It is made with leather. If the rear end has lube in it yet, then the gears should be fine. I would advise getting a parts listing and installation/driving instruction booklet from one of the peddlers. Those are commonly available for the different year C's.