I put Eaton replacement HD springs on my 67 fastback, must have been 1988 or so. Ride height is still good, but I'm thinking the bushings need replacement. Out on the road course the rear seemed a little loose.
I was also thinking of adding another half leaf to the front half (this stiffens them for launch and roll, without affecting the ride). So taking them to a local spring shop seems the ticket. Of course, this is around #17 in my list of things to do.
