Two questions: 1) Anyone running Edelbrock IAS shocks? Other than the $$$, like'em or no? Worth the $$$? 2) What was the OEM spring rate on a '73 K5 350/350? According to the sticker in the engine compartment It came from the factory with the "Heavy Duty Front ST" option. (not sure if that's refering to the springs, shocks or stabilizer ) I'm planning on putting in some new springs all the way around and want to get an idea of what the new ride will be like given the different spring rates on the aftermarket kits.