Aftermarket fuel rails

[Cadehall234]

Hello, I have a 98 mustang gt with a return fuel system. I am installing edelbrock fuel rails on it and I’m not 100% sure how to run the fuel lines. Correct me if I’m wrong but I believe the line running to the regulator on the rail is the feed and the one next to it is the return. Do I have to run a y block on the feed line to hook it up to both fuel rails or do I have to run the feed to one rail and the return to the other