Are you thinking of using the 35mm SLR body as a replacement for something like a Packard shutter (and removing the SLR's back), and still exposing 4x5 or 8x10 film with the rig, John? If so, I think the size of the 35mm film gate would be rather limiting.

I have seen adaptations that mount the 35mm SLR (or, digital) on the rear standard, with the objective of exposing 35mm film (or digi-sensor) using the view camera and lens as the front end.