I'll chime in with my 2c worth. Modding lenses and adapting to off-brand mounts is something that particularly interests me. As I see it, you will run into some issues adapting a Takumar 50/1.4 to F mount.
The design of the Takumar is such that it does not have a separate, removable lens-mount flange like a Nikkor does.
The rear part of the Takumar lens incorporates the aperture stop down mechanism and the aperture auto/manual switch. To fit an F mount flange would require modifications to the aperture mechanism of the Takumar and the removal of n+1.03mm (where n=the thickness of the new mount and 1.03mm is the difference between the Nikon and M42 register difference) material from the rear of the lens body. An engineering challenge, but if you have access to a machine shop, I can't see it being impossible. On the plus side, the Takumar is a reasonably simple lens to tear down.
The second, and potentially insurmountable problem its the distance the rear element of the lens protrudes into the mirror box at infinity focus. A standard Takumar protrudes 8.3mm from the flange at infinity. This compares with the distance the rear of an AI lens at the same focus setting; however, once the mount has been changed, and the lens's infinity focus has been restored, this moves the rear element
further into the mirror box, with the potential to foul the mirror when it flips up. (As an aside, this is the problem that's so far prevented me from converting the Minolta MC Rokkor 58mm f/1.4 to F-mount, something I'm
very keen to do.)
So that's how I see it. A challenge for sure, but you may just be able to pull it off. Good luck