Hey spatts-
I remember reading somewhere Dave Tate recommended using an inflatable mattress or air pillow under your hips. I think he said this was to to teach them to keep their midsection tight and keep the work on the correct muscles or some crap, but it might just help with your bruising and have enough give to be effective.
Let me know if you try it.
BTW, is Hannibals RevHyper a wooden or steel unit. As soon as I get my project in the garage back together, I plan on building me one.
Later..