Problem resolved. I figured out the solution.
I combed the LIberator website for position illustrations applicable to the wedge, ramp, or wedge/ramp combo. I found 67 of them, although I'm sure some are the same position with different illustrations, and some of the illustrations are so crappy I can't tell if the position was designed for straight or gay couples (I eliminated the obviously gay ones).
Printed them out on cards, and handed them to my wife. I told her if she is interested in any of them, just hand me one, kindof like sex coupons. No uncomfortable sex conversation required.
Perfect.