Fuel System Help

So bare with me, I'm new to this :)
I bought my Duster and it had and electric fuel pump mounted on the rear frame plumbed inbetween the existing lines of the gas tank and the origianl metal line that runs up to the engine bay.
I'm not sure what fuel pump it is, but its leaking, and has always been very loud. I think its a summit brand (thats whats on the mounting hardware) and has what looks likes a metal base plate
bolted to the bottom of it with a rubber gasket under the plate, thats were its leaking. I tried to tighten up the bolts but no dice.
Anyway, looking to get a new pump and possible run a return line but i'm not sure the correct (read safe) way to do this.
I have a vent line that looks to be unused, it runs along with the feed line into the engine bay but is not hooked to anything. Can I use this for a return line? and should I plumb it into the piece
of hardware i've outlined below ( the regulator I believe) Like I said, this is new to me.