I installed a front disc conversion kit with power booster and new master cyl from CPU car parts. Works great, conversion was easy, just needed a few special brake line fittings to get it all together.

If you are interested, I have a spare set of new stock height spindles, caliper adapters and backing plates that I could sell you. They fit a 68, but I think they should work for a 69 too. Someone here will know for sure. Not sure if they will fit the 14" rims as mentioned earlier. After those parts, all you would need are rotors (with bearings, seals, dust caps, and spindle nuts), calipers, brake lines, master cylinder, proportioning valve and a power brake booster. I heard that parts for the Camaro from your local shop will work.

Good luck, let me know if you are interested in these parts.