Rover 12 clutch replacement

[Simonk64]

I have recently attempted to replace the clutch in my 1936 12 and came across an issue with clutch not releasing.
The car was troublesome last year when selecting gear but liveable. Put the car away for the winter and in may tried to get her out for a run but the clutch was completely locked up. After trying to free up the clutch with the car up on jack stands I decided to pull the gearbox. The old clutch and toggle springs were in bits in the bell housing. So new clutch, pressure plate and trust bearing ordered and fitted.
However the new clutch and pressure plate are thicker than the old units and on fitting I noticed there is no room for the plate to release when bolted down on to the flywheel. Having spoken to some older mechanics I know, they recommend shims on each stud on the flywheel. Not something I've come across before.
Has anyone come across this issue before?

[GOY189]

Have you spoken to the supplier? If memory serves, 1936 cars had a pressure plate with 4 fingers. If the new clutch has 3 fingers, some modifications may be needed. I haven't come across the shims advice before.

Mike