Your glow plugs will only stay on for 0 - 120 seconds depending on temperature and conditions so if you're going to use a test light you need to do it quickly first thing in the morning.
If you have a cooler on the transmission I don't see any reason it won't handle that weight. I have a manual tranny so I can't speak from experience on that one though.
As for repairing the leak at the fuel bowl here are some instructions.
Separator Valve Rebuild
