[spacemanspif]

Since you don't care about the MPG boost in theory you could connect your pressure line to the return line and the pump will free pump constantly but has some concerns.

1) not sure the pressure while the pump is on bypass mode
2) not sure the return port can flow enough to keep the up "unloaded"
3) reduced oil capacity means the pump will heat the fluid faster
4) fluid might get hotter but I'm not sure of the inherent cooling of a fully functional system

Keeping the pump and looping the lines and looping the lines on the rack will create extra complexity for no real gains. You will be just as likely to develop leaks with or without power assit since you essentially plan to retain the entire system. Without deleting the pump I THINK you are basically chasing your tail and it will be more worth your time to fix the system than modify it with your current plan. Of course, you are welcome to do whatever you wish I am simply inputting my $0.02