Correct me if I'm wrong, but the only reason they require a return line is because they're using an in tank pump.. the edelbrock sump is a universal kit that is advertised for use with all efi systems..
Just out of curiosity why does no one use the universal sump kit from edelbrock? It seems so much simpler. No return line or in tank fuel pump. Easy access and keeps your mechanical pump.
The fact that this comes complete with the distributor and an affordable sump system it looks like a real winner. No need for return fuel lines and can keep the mechanical fuel pump.