I have not had a reason to check out the Caparo numbers on the Alternative Parts list, none of it has worn out yet. It seems that Caparo once was AP Lockheed but now don't sell to the public, only manufacturers such as Morgan and Aston Martin. This means that any part numbers don't appear on cross reference list either. Assuming that the Caparo part designs are very similar to the Lockheed, that may be a good place to start looking at detailed specifications on dimensions. Sorry I cannot be of any further help. Please let us know if you find a good substitute, I am sure a direct replacement is there somewhere. The Caparo information says the clutch cylinder is 15.8mm diameter which is 5/8", so suggests an "old" design.
