So I picked up another set of parts off ebay the other day...
left and right...
calipers
brackets
rotors
knuckles and hubs
hoses
abs wires
as usual I unpacked them and started to look them over. everything looked fine so I decided to clean up the calipers. scrubbed them down and power washed them. took the brake lines off and drained the remaining brake fluid out of them and didn't like the look and smell of the fluid. no biggie... popped the pistons and seals out of them and cleaned everything out. bores were fine (no rust) and the pistons and seals were in good shape. reassembled, filled with some left over superblue and sealed the holes with foam plugs. then I turned my attention to the brackets. took the slide pins and dust boots off, cleaned everything up and relubed and reassembled them. that's when I discovered it. as I pushed one of the slide pins back in and worked the grease around I was surprised to see grease in places I hadn't touched. it turned out there was a HUGE crack that split clear through the slide pin bore and along the bracket itself. you could actually see the crack flex if you applied a twisting force to the bracket. that one went into the trash. I don't even want to think about what could have happened of that bracket were on my car.
also found the left hose had a pretty good split in it. it didn't leak under an air pressure test but it was cut and bulging. it's also in the garbage already.
just a friendly reminder to everyone, check over your used parts carefully.