The DB shutter clips on to the back side of the front carrier frame, where the bellows would normally clip. Then the bellows clip to the back side of the shutter body. Using barrel lenses with this shutter requires mounting them on extended lens boards, which are the opposite of recessed lens boards; the extension is necessary to clear the ass end of the lens from contact with the shutter blades.
Is your DB shutter adapted to fit the front of your Cambo carrier frame? If so, the easiest option would be to get just the carrier frame from a SINAR, and mount all your barrel lenses on SINAR lens boards with extensions. It will be a bit front heavy, and you will have to be very attentive of your tilts and swings, as the nodal point of the lenses will be so far in front of the axes of the swing and tilt. It will be similar to using movements with a telephoto lens, though probably not as extreme. Using a SINAR with the DB system installed as intended is already a bit like this, but having the lens even farther forward will require even more care when tilting and swinging.
Personally, I would can the Cambo carrier frame and just make a SINAR carrier frame integral to your camera.