I bought a few days ago a Zeiss Planar 45mm/2 (for the Contax G cameras) that has been adapted by Jim Buchanan to M mount. It cost me $750. I have such a lens in Contax G mount, and like many users of such lenses, I love using this lens as an AF lens on a film camera.
I tried out the Zeiss M lens on the M8. I was curious to see whether the 45/2 would perform as well as it does on the Contax G.
The lens seems to be housed inside a Minolta 55MC, using a Hawkes adapter for the helical. Jim reworked the helical with new lube and he black anodized it. he told me that such conversions take a lot of time.