I looked at Wilwood brakes but the kit is like $ 3600 :-/
Since you have 20s, have you considered doing a brake kit conversion?
I just got custom caliper brackets to install C6 ZO6 calipers and Baer 15" rotors up front. No real need to upgrade the rear where its not a racetruck.
The ZO6 or GS calipers are $264 ea on Rockauto and the rotors from Baer are $250-275 each. The can used the same brakelines you already have, just need some new crush washers and Banjo bolts for the new calipers