"I think one was to shim the front of the crossmember...anyone seen this thread?"

I don't know what the thread had to say on the subject, but I believe you gain positive caster by adding shims to the rear of the crossmember, not the front.

FWIW, I've never used this method on my 142 race car. I usually run about 3 degrees positive caster, using only the upper a-arm shims to accomplish. I've never broken a bolt and the current ones have at least 6 race seasons on them. I'd wager there's more stress on those bolts in an afternoon of racing than in a lifetime of typical street driving.

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Gary L - 142E ITB race car, 73 1800ES
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