They should work reasonably well on the v8 but driving them could be a bit of an issue. The important thing about a supercharger is to mount them solidly (no movement) and align them perfectly with the pulleys. If you dont the belts wont last long (if you can keep them on at all).
Max RPM is somewhere around 12,000 but keep it under 10 for extended periods to be safe.
An easier option that you might want to consider is a turbo set up. The positioning of things is far less critical.
Having said that superchargers rule. There is nothing better than the linear power they give you - its like having a bigger engine.
Expect this project to cost you twice as much as you think and take 3 times longer tho