Hey all! Wanted to provide an update.
We got it fixed! It did end up being the fuel pump. Found a local auto/truck shop that was able to do the repair for us at less than half of what the local rv shops were quoting. Due to that we also ended up getting some new tires from the same shop as well.
We just got back to Colorado after a 6 week trip to visit family in Michigan for the holidays and only had one issue on the way back. We threw a check engine code for MAP sensor high vacuum, stopped at a Napa and inspected the hose, no issues with the hose, boot was in perfect shape as was the hose. So I ran inside and purchased a new MAP sensor, figuring the cheapo one I installed a few months ago probably died out.
So we continued down the road, made it about 2-3 hours, and started getting an intermittent stutter/loss of power. No CEL, engine sounded fine, transmission still shifting smooth, no noticeable issues. As we were about to pull off at the next rest stop, the issue stopped. Did a relatively quick inspection of the engine, fluids, etc. and nothing seemed abnormal. Had lunch and continued down the road about an hour later.
Made it another roughly 2 hours and started stuttering again. Stopped and checked again, this time for about 10-15 minutes and found nothing so continued on again. Once we stopped for the night I started doing some research and found that a faulty EGR valve can cause a false code 33 and/or code 34. In the morning I did a quick tune-up (changed plugs, checked wires, checked cap/rotor, and changed fuel filter) continued down the road and once again about 2 hours later it started to stutter again!
Stopped once again and my fiancee had the thought of, the stutter didn't start until after changing the MAP sensor. So we put the original one back in, and no more issues other than CEL again for both codes 33 and 34. Obviously I can't have High and Low vacuum simultaneously so I am now thinking the EGR valve is faulty. This is very possible as it is the original EGR valve from 1990, so I will be replacing that and will report back if that resolved the CEL!
But the best news is that we are up and running and have new shoes! Now just to fix the genny and we will be fully up, I am thinking fuel pump/filters on the genny, also need to do an oil change.