Wonderful suggestion newarts and Rico.
I was starting to go down that direction, since none of the other adapter combinations really would work for me. A 13 mm C/Y extension tube (found one for about $20 at KEH) would probably be the simplest, and then use Rico's patent pending chopping method using a Dremel on the camera side of the extension tube C/Y mount, turning it into a modified Pentax K mount.
This appears to be very effective for Macro use 1/3 to ~6x. With the added extension tube magnification, I am estimating that the widest focal length for tilt shift operations would be on the order of 45mm.
The bellows does appear to be pretty cool in the tilt shift configuration. Probably need to try this some time, however not really into Macro.