Thanks guys.
Gerald, my 12V compressor is in the front cap, just inside the small access door on the front of the coach. Next to the hydraulic pump. And yes, it is an HWH system. I'm not sure if the compressor is working as I have not had the chance to level using the air suspension, and leaving it, like in a camp spot situation. It does appear to be in good condition and is very protected from the elements. If it's not working, it's probably due to non-use. Where it is parked now, next to my house, there is a down slope beyond the limits of either leveling system, so I have left it alone. I have a trip coming up at the beginning of April, so I will be able to put it through its paces!
Joel, any info that can prevent me from doing something stupid is always appreciated.
I think I'll create another post telling you all about this coach. I'm sure you all have some very sound advice that goes beyond welding and leveling!