In regards to the cam drive question, it's an option from most cam suppliers to have the back of the cam drilled and tapped for the rear drive. Most engine builders are capable of doing this as well, a couple of supermodifieds I've been involved in have had to get cams drilled and tapped because they didn't originally come that way.

You don't have to run the pumps off the back of the cam, but most people do. In a sprint car, it is definitely more convenient to run the power steering pump off the back of the cam because it greatly reduces the amount of plumbing required vs. a belt drive pump on the front of the engine.