I have the file saved somewhere (and couldn't find it) and can't find it in a search. It also coul have been on CAC - I saw it way over a year ago and it itself was archived....
Basically with very little machining - a step or groove or somesuch on the fronts and making some bracket or something on the backs this guy claimed a 100% bolt on use of C5 brakes, without the ABS system.
I do not recall if the p-brake/e-brake was retained or not.
The Wilwood is one conversion I've heard of. VBP claims their top line rotors (C3 rotors are something like 11.7", IIRC) and their new calipers, the Wilwood system only develops about 10% more clamping force. I personally would just love to dump the damned live piston design, whatever high end system was used.
I love VBP's suspension stuff, and have their ultimate system on my POS, but I had a nightmare that stretched over $3500-4000 and 75,000 miles or more and couldn't get the same braking I get out of four wheel drums on similar aged things - and I used lots of their products, although not yet their creme de la creme rotors. Just recently, during this horrible year of engine (mainly) problems, did I finally get decentish - but I would not call even good - brakes. I rebuilt the VBP calipers with their kits myself, changed the @%$#%$ distribution/proportioning valve I *ALWAYS* suspected was causing problems, went with the Hawk pad type they recommended and changed master cylinders yet again.
For the first time, after trying all kinds of fluids, 7 master cylinders, 6 rotors, 6 calipers, flexible SS and other new connector lines, did I finally get reliable braking, albeit not sportscar level to my thinking.
I hate working on brakes, having grown up on drums and dreading all the little springs and rusted parts and whatnot, but when I sat down and just did it myself - and all at once - I got results. (I do not feel I broke in the pads perfectly....I basically followed the procedure, mostly, pretty much...."klaatu, verata...nick<cough>"
Now SSBC offers a bolt on high end C3 thing called "force 10". One person here or on CAC, who was quickly backed up by others, by the moniker of "Megladon" had a terrible support problem with them I thought was reserved for the clowns who put my engine together.
Baer also has SOMETHING - but I never found what that was. It may only have been 6 piston calipers, I'm not sure, I never did trace it down.
My advice is whatever system you go with, use high boiling DOT 3/4 - super purge it with the very same type (FoMoCo DOT3 at the minimum or one of the racing types like Wilwood), do EVERYTHING on the system at once (I have never changed main lines...), change the flex lines to braided SS and make sure your MC is the right diameter (1" or 1.125"). Finally, once done, have that puppy powerbled WITH THE SAME FLUID, preferrably twice on two consecutive days. (When using a specific fluid - you'll have to pay to charge up their whole power bleeder with it.)
I finished that chore last fall and it's held with no addressing since then, which, when I think about it, scares me.
Good luck on the worst designed part of the C3!