There is no difference in fuel pumps. The regulator controls pressure by returning the excess to the tank. Just because the pump is capable of 43psi doesn't mean it has to run at that pressure. Look up a pump for a 88 Dodge 318 TBI and a 92 Magnum. Same pump. The GM TBI has the regulator built into the back of the unit. Only the 454 one was adjustable with an allen wrench, which is the same unit Holley used for the Projection 2 bbl. Run what you have, it will work just fine.