Thanks for the info guys! I run them back to the tank in my own boat, so that's what we'll do on this project!

Ive seen a fitting that goes into the main fill line between the tank and the fill port.....it has a side port to tap into for the return line.

https://cimg4.ibsrv.net/gimg/www.off...f51857ce08.jpg

Yup, that’s one ^^^^
Here are 2 more:
https://www.cpperformance.com/c-500-...s-returns.aspx

On my velocity i had two fittings in the tank. I just used the second fitting to run the fuel back to the tank.
I've also used one like this from hardin marine https://www.hardin-marine.com/c-500-...s-returns.aspx
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