I just modded R31 in tank setup mount and all to fit a ute tank in the section opposite end of sender. Just pick up a R31 tank and remove what you need I used the stock R31 baffle/swirl pot to. Only 2 things other than mounting bracket and baffle i had to do. Extend the bracket, wires, connecting fuel line. So pump sat closer to bottom and had to cut a section out of my tray above pump setup as it was hitting on the low point in tray. But it had to be done anyway to access it without removing tank just fabbing up a cover that screws back on out of 1 mm sheet. Also i only used the wires for pump positive and negative and kept my original sender in and wiring. You end up cutting the vapour line out but i gently bent the old fuel line in the tank towards the vapour line connector and it went straight on there when i refitted it. I used a bit of 4mm inch wide flat at back end of tank ( tail gate end) to space the tank down a little marked and drilled holes of course for bolts to go through and used slightly longer bolts.

Yes i am i got a 71 ute with a a15 which im converting to efi with a factory a series efi manifold

I don't believe so. I've got an 1985 ute and it didn't have a return line. However it did have a vapour hard line to the charcoal canister that could possibly be adapted.

Are you wanting a return line for an EFI conversion?

Did the late 78 up ute tank had a fuel return