[Blas]

Older SPF's do not have a bolt on the shorter side of the rollbar. Newer SPF cars have a bolt added there because of a reported squeaking problem. I just replaced my original roll bar with the taller version. I added a large 'O-ring" on the body pin to prevent any squeaking with the new bar (my original never had a problem). So I agree with the others that your noise is probably coming from the rear suspension. Lube it up, one side at a time to see if you can locate the problem. Right top - test, right bottom - test....etc....