mounting an electric pump

They want you to mount the pump inlet and outlet lower than the fuel tank.
Preferably frame rail.
You can cut a hole and run a grommet outside of the trunk for a braided flex line to your fuel filter then plumb flex or hard line to your pump.

I've gone through several electric pumps including a super quiet Holley hp125 wich was great for a year until it fizzled out.
I am now running a cheap summit pump that sounds like a pissed off wolverine and I have a Jegs back up pump in my trunk for emergencies which I've already had to use when my pump burned out at a cruise in.

I am seriously thinking of going back to a mechanical fuel pump.