Bolax
+1y
The return line goes back to the tank, not the pump. Here's the whole layout in simple terms:
1. Fuel cell spout #1 to inline filter
2. Inline filter to inline pump
3. Inline pump to OEM fuel delivery line
4. OEM return line to spout #2 on fuel cell
That's it. Then you'll need to power the new pump of course. The easiest way is to use the OEM fuel pump power and ground wires on the new pump. At that point it should run just like it did with the stock tank and pump. Just remember, fuel isn't something to play around with so do it right the first time. Route the lines carefully and mount everything securely.