Don't know if you where able to run the (3mm??) Webasto fuel line the last 24" into the tank.
When I've done this before I used a compression x 1/4"MIP (pipe thread) connected to the tank and another compression fitting on the end of the tube. The weight of the second fitting hold the tube down so it sits on the bottom of the tank.
This is where I've had my head stuck for a few days, Propex heater (not finished), heating ducts, pumps, pump box, floor supports is all new
