not sure what you mean by regulating the fuel AFTER it enters the carb. but yes definatly have the regulater before and as close to the fuel inlet as possible. if running duel tanks and at the same time, make sure you run equal length line from each tank to the pump. i ran one short and one long and it drew fuel from one tank faster than the other. same with the return line/s. run two returns, one to each tank. alot of plumbing yes, but it works the best.