If you go to Summit racing you will see there are different types of electric water pumps. They pump from 20 to 55 gallons per minute.

Once you convert to an electric pump, that draws 6 amps, you decrease the mechanical load on the engine. The altenator does not have to work any harder to create energy then it did before. What happens is less drag on the engine = HP

As to using a oil cooler and custom radiator. That is the way to go. Your racing your car and providing proper cooling to both liquids very important to your engine "oil and water". I know that I am going with the radiator you mentioned. Im already am running a oil cooler from Tomei and the Oberg tattle tail. Im glad to hear it works. As you can see by my pics my radiator is very small. (webbs1200)

Some of the reasons not to use the pump make no sense to me, but the bottom line is that everyone has some very valid points in regards to this subject.

I would say the key to the origanal poster would be find a way to make way for the radiator to receive the proper air flow it needs.