Thanks for advice. I'm cool w/ my single piston 12" brakes. I have 18" wheels, so if I upgrade, it will be a 13" something.
Scottydoggs, I know zzp doesn't manufacture the parts, but I also believe if I just bought fbody, or ctsv brakes, & tried to put them on I would have a problem, starting w/ OE brake lines, but more importantly for me is to have correct bolts &/or space rs, shims, whatever. zzp puts together a kit that is a direct bolt on, w/o trips to store, that's what I paid for.
And that's what I was asking about, the bolts, not the caliper itself. Believe it or not, I actually understand the difference, & made the purchase I wanted.
So I answered my own question, about the slide pin.
http://i1172.photobucket.com/albums/r566/Mister_De/Mobile Uploads/IMAG0736_zpsamzngalg.jpg
Top is from jy off 12" single piston 05 MC (N/A)
Middle is off the 12" single piston 'upgrade' that you all are hating on.
Bottom is OE from my 11" 03 GTP.
If anyone cares, GM 11" & 12" caliper have same slide pin. My after market bent pin has a rubber sleeve @ bottom that give it same outside diameter as upper portion of shaft. it's bent right where it narrows. I'll only use solid straight slide pins in the future. And next time I have the other wheel off, I'm changing those to solid straight shaft slide pins, too.
I'm mind boogled! & happy! Finally, quiet & smooth up front! It was a knock or clunk, when engaging gear, changing momentum, low speed braking or hard acceleration, similar to what a broken sway bar sounds like.
Red, thanks for the big pic, now I see the squirrel upgrade. You must have good brakes, I don't know squirrels that roll out w/ crappy brakes.