Re:Steam Table issue
Are you using a sizeable generator?
I got electric food warmers at restraunt depot for 99$ they run @ 1500watts max. ! or 2 on a decent sized generator would probably suffice.
if you are determined to use propane you could save some cash and build one from a low pressure turkey fryer burner. I have one on my food cart that works perfectly. I barely turn the thing on to keep the water hot. I only use one burner for one full size steam table pan and use dividers to hold 6 pans in it.
I used black iron pipe from the local ACE and fitted it to a replacement BBQ propane line. I actually have two burners, one for the steam table, one for my griddle, and a water heater that is supplied from a single 20lb tank. You could definitely do something similar on your truck.