The bolt holes are 100mm center to center on the viper caliper. I'd have to do some fancy measuring and math to get the distance from the top of the pad radius to the bolt holes.
I did some comparing between them and even if the height was the same, the distance from the back of the rotor to the mounting lugs looks completely different. I think it would take a completely different bracket to make the SP calipers work.
Maybe when I buy my next set of tires I will look at it again. I will probably need different rims to fit fixed calipers and could just swap them all at that point.
