Sorry I wasn't clear in my post.
I've a Spitfire 1500 with a lean on the rear off side. This is noticable from the rear. If I reverse the lean changes to a very upright car with postive camber.
I've renewed the spring, using a standard one, and the diff (because of a rumbling sound) and trunions. This made no difference, although it rides better.
I'll try out the test discribed and advise.
Peter