To answer the Corvair in an aircooled VW question, if the VW is swingaxle, you can flip the ring gear. If its IRS, or if you choose not to flip the ring gear, there used to be reverse-rotation cams available for the 'Vair - not sure if they are still out there, it's been a while since I was really up on this swap.
V8 'Vairs usually run a radiator up front, cut the valance under the bumper for intake, and either vent out the wheel wells or vent the hood. I have seen one or two with the radiator in the back, with scoops, but that usually looks funky.
Another V8 swap that's out of the ordinary used the Olds Toronado transverse powertrain.
