I've nearly had one of each chassis (or two or four) from the 1960s through the 1980s at one time or another. Goodyear Regatta II (review, prices) or Kelly Charger . Trust me.
Firestone Affinity LH-30 with UNI-T (review, prices): I have been installing these on nice colectible SLs, Cabriolets, 6.3s and simialr cars. Give these a shot; they work very well.
Piet van Rossum