I have a 1963 Chevy ii. It is a convertible, and it is a stock vehicle with the exception of upgrading to a 10 bolt differential out of a 1965 Chevy ii and moving from 13 inch wheels to 15 inch wheels. Because of the wheel and tire combination I have got very minor rubbing of the rear tire against the quarter panel. Just barely touching the sidewall. Here’s my question. Have the original Springs from 1963 in the rear of the vehicle become more relaxed and therefore lowered the back of the car even just a little bit? If so, could a guy purchase new leaf springs that are stock replacements and gain that little bit of height I might be looking for. All I’m looking to do is have the vehicle at stock height. Have you ever heard of springs becoming less springy and lowering a vehicle over the lifetime of a vehicle. 1963 Chevy two convertible. Also, where would I go purchase quality springs?