Originally posted by Steve Beswick I didn't want to go with the k mount variety because I use it a lot of the time in av mode.
then honestly I don't know what to tell you. there is no way to modify any Takumar 1.8/55 to mount and un-mount like a Kmount lens without loosing infinity focus, unless you do some serious surgery to the mount. which may not be possible either and really not worth the trouble and possibility of completely destroying the lens.
maybe you should look into a lens with a similar focal length and max aperture from another brand in m42 mount? you may find one that has a base large enough to 'notch'. it wont be a Takumar, though you know that. the simple fact is, that its an m42 lens and you are trying to use it on a body designed for use with AF K mount lenses. just about all Takumars are too small to 'notch' (in my opinion, that's a good thing). you can either deal with the limitations or not use the lens. I wish I could help you, but I just don't believe there is a way to achieve what you want.