Coilovers stress an area of the frame that's not designed for load bearing, unless you do a lot of re-engineering of the crossmember where they attach. You need to realize that the S-10 body weighed somewhat more than the one that you're running now, so it's not surprising that the ride is tough. You need softer springs, supplied by one of the race car supply places like JEGS, Summit, or one of the other custom suspension vendors. If you're not able to do the suspension travel and spring rate calculations yourself, see if you can find a local round track racer to help you out.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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