I have a caliper that has some corrosion. I can send to PMB but before I do looking for options to save it myself. The issue is the corrosion is causing the seal to leak. Thoughts?Click to view attachment

Pretty much every S caliper has some degree of corrosion. However, the seal is between the Rubber ring and the Piston. The state of the bore is of less consequence. Now the pistons generally will corrode badly, so what do they look like? Almost every S caliper needs new pistons, and of course the seal kit. Re-anodizing the calipers does help a lot.

I have new pistons installed from PMB and the seal kits as well.. It leaked.. I did scrape some corrosion out and maybe that will help.

That IS rather an odd situation Ben. I suppose if the groove is crappy then fluid could escape behind the O-ring. I always ensure the O-ring groove is perfectly clean before installing the rings. Please keep me posted.
Dave