I've got a 73 that I just spent a day in Hollister Hills SVRA with. Lots of fun, but the thing was noisy...even minor articulation caused creaks, groans, and a couple of loud BANGs! What's causing this? Worn bushings? Worn weatherstrip? Worse? How hard is it to replace suspension bushings...is this something I should hold off until I'm ready to do a lift?