The idea of milling off the close focus cam of a DR 'cron sort of horrifies me. I can understand wanting to use the DR with other cameras. I mean I love my DR- it basically lives on an M3; both are with me most of the time. But jeez; if you want to use one, why not get a camera that fits it? If you want the DR's look in your images, but want to use a camera it won't fit it, why not sell it to someone who wants one intact, and buy a rigid 'cron from the same era? After you've paid for the mill work, it'll probably cost you more to own the modified lens, and for what? The glass and coatings in the DR and the rigid are the same. Once that lens is taken apart, modified, cleaned, re-greased and re-built, that marvelous "Leica build quality" will feel and behave the same as a rigid cron after a CLA- which will still be nice- but it will no longer be the thing it was. Why destroy a lens and waste money in the process?
I said "sort-of" horrifies me. I'm not religious about it; this "it will no longer be the thing it was" concept may or may not be important. If a thing will work better for you, why not? I do have the goggles for my DR; I rarely use the close focus feature. So why not? Do what you like. But personally, I think I'd find another lens/body combination to shoot with before I'd spend $ to cut the cam off a DR- there's no surfeit of wonderful, classic 50's out there, not to mention bodies that fit the DR.