Hi all, I recently ran across a Komura preset 135mm f2.3 lens. It currently has an M42 mount attached, but I'd like to switch it to either a Leica M mount or a Nikon F mount. The M42 is attached with 3 set-screws and would be very easy to change if I could find the proper adapter. I am not interested in using a Nikon to M42 adapter, because I either lose infinity focus or have to add elements to the formula, neither of which seems a good option. I have grave misgivings about the quality of glass in the M42 adapters. Any ideas?