Caliper info

I have 2 sets of calipers. Dont know which to use? Or buy a new set :)

First set (just painted them black) came with my car, looked new and never used. I think they just need a piston but in not to sure? Second set (daughter wanted to paint them red) came off a 1988 diplomat, they just need cleaned up I think.

Calipers are the only thing I have not purchased new because I had 2 sets. Should I just buy new ones? Diplomat ones from the auto store or should I just clean mine up?

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