As I've said many other times, in several other threads:
I got my larger-piston extended-cab calipers by complete chance, from my favorite Treasure Yard. By total coincidence, that happened to be the truck that was being prepared for the crusher that day, so removing the entire front suspension was no real loss to them. Wasn't until I got the parts home that I realized they were bigger/better than what was on my truck. I had to go back for the master cylinder and booster after I figured-out what was going on.
Pulled 'em apart for cleaning and inspection, put 'em back together, and they've been in-service on my '88 K1500 for many years.
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"Crust" on the square-cut seal, partially-removed with a fingernail. Seal was otherwise in usable condition.
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Going back together with the seals and mounting pieces lubed.
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