any one added an extra fuel pump to a 7.4 fuel injected mag to help with the vapor lock issue the boat is a 1997 baja wondering about the oil pressure cut off and if you could wire into the system to get that purge when you turn the key on

I added one to my old 2006 Crownline 202 LPX with that same problem. I installed a Holley Marine rotary vane pump with a 3-way valve. Your stock pump is designed to "push" fuel and when vapor locked will only sit there and spin until the fuel, mainly the Ethanol in it, condenses. The rotary vane pump is designed to suck so it will just push the vapors past it until it gets liquid to it. Once that happens and the liquid is to your stock pump your engine will crank just fine. The rotary vane pump will never replace your existing pump as it will not get the pressure high enough for a fuel injected motor, but it is an excellent backup to the vapor locking problem.

Hope this helps.

How did you go about wireing it into the system want to avoid cranking the motor long enough to get the oil pressure to let the pump start

I had an extra rocker switch on my dash that I used. I would turn the rotary vane pump on until it built pressure up, then cranked the motor and turned the pump off. Worked like a charm.