Looked into a few discussions on the good ol interweb... seems the consensus leans towards not needed a return fuel line, I think from what i read, if you have a regulator it's keep the fuel cooler which is what the return line in theory is supposed to do.
Regarding my previous note about it being mounted below fuel tank.. I called Summits tech line and the guy helped me find a pump that is self priming (pull/push) so it's ok to mount above tank.
https://www.summitracing.com/parts/sww-82091
None of the pumps listed online have no description if its self priming or not.. I think they refer to it as a "lift"