so after tons of research, measuring, this and that, the Arrow performance rod for the F10 M5 will fit the 2010-2012 s63 (original, not the TU) with modifications.
First, the rod bolts touch the block/lower part of the cylinders and need to be notched to look like the TU block. We installed the rods, saw where the rod bolts touched the block, outlined with a sharpie, and grinded/ground the block with a carbide drill bit.
Next, the s63 "S" shaped oil sprayers do not fit and need to be removed and the ports plugged.
Finally, we are looking into putting a notch on both sides of the rods to allow oil to escape up into the wrist pins.