Teahead, you can always call those guys and ask about modifications.
I did read the article by Murray Waite. Funny however, when they mention that the car was too far gone for a purist restoration but when they mention what was done, the major panel work and parts replacement, they could have done anything. It's not as if they just shoehorned a bigger engine and better transmission into an old and tired 230SL, they did a major nuts and bolts, rotisserie-style restoration. It could have been a restoration to bring it back to "purist" specifications.
The firm in Michigan that has worked on my car over the past has done a number of engine/transmission restomods. An M5 engine into a BMW 3.0CS. A V12 ex-SL600 into his own W126, and the same into a first generation SLK. These projects are not for the faint of heart if you are doing them yourselves, or if you are paying someone, best to have deep pockets.
In the case of modern into old, such as those SL600 engines/trannys, there are a lot of mods that must be made electronically; these major parts are controlled by ECUs and they are tied to the VIN. Takes a bit of work to sort it all out.
