[Bruce Edwards]

If all else fails you could cut yourself a set of shims out of thin steel and coat it with anti-squeal and then install it between the pad and caliper.
The trick is in getting the pad backing to stop bouncing off the caliper pistons.
I am building a ERA with Wilwood brakes right now and will take a close look at the preassembled caliper and pad unit after hearing all the trouble you two are having. If I see anything funny I will let you folks know.
Good luck with yours and let us know what works.