Magnum injector to carb swap, fuel pump question

Do you want to keep the serpentine belt system? I believe, if you do, you have to go electric. The La style timing cover will not work with the serpentine drive.
On a 87 dakota I have, I just use the carter rotary pump. (4070 I think) But pressure is low, and does not require a pressure regulator.
Also, for safety, you can use a pressure switch, which is what they recommend. https://static.summitracing.com/global/images/instructions/crt-74773m.pdf