Recently, I made an adapter that allows me to attach my Phase One P25 Digital back (that was made for the Hasselblad V camera) onto my Rollei SL66 camera body. With some small modification to my Phase One P25 back and almost no modification to my SL66 body, I can hold the digital back in place. The sensor of the Phase One P25 back can be placed just inside the film opening of the SL66 body, thus allowing a full use of the sensor (37mm x 49mm), although the sensor had to be located slightly off center of the lens axis. I suspect that the amount of the offset might create some degradation of the picture, but it seems small price to pay for the ability to use all lenses and virtually all attachments in my Rollei SL66 collection.
I will post a few pictures to demonstrate the set up I described above. I am happy to share all the information about the adapter with any member who is interested. I hope the idea would allow us SL66 fans to enjoy our camera system and perhaps we can use it more and make more pictures...