I have the same question, I ordered one too
I want to use the standard Sierra pump and sender but not sure if that is possible until I have a look at the tank and pump. I think that it may not be possible as the pump needs to pick up from near the bottom of the tank so some creative engineering may be required. Sorting out a return is dead easy, it's just a pipe inlet, if using the standard submersible pump the return is built in to the mounting plate, the same as the outlet pipe. Hope that makes sense....