I'm resurrecting /6 #2292 finally, and the brakes are going to get the full PMB treatment. The previous owner had put 911 front calipers on the back, but I picked up a couple used calipers years ago that were purported to be from a /6. They came with the spacer for vented disks, which was a real bonus. I bolted the passenger side up, and things look like they fit pretty well. Excuse the rust, all of this is going to cleaned up or replaced.

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This looks like it should work, I think. But for the driver side has the bleeder on the bottom of the caliper, which I'm pretty sure is a problem.

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Are these Ferrari 308 calipers? Can the one caliper be drilled for a new bleeder?

thanks,
Guy

Get a piece of wood the thickness of the rotor, unbolt the caliper, jam the wood between the pads, flip the caliper upside down and bleed the caliper.
Bit of a PITA but it works.

Seems as though you are correct, maybe 308 caliper.