I have a 7500 and did a test this past summer at the FMCA rally in Gillette Wyoming. I filled up my tank before the rally. Went to the rally ran the generator 78 hours left the rally and filled it back up I averaged .25 gallons per hour
I was there in May no appointment, order 5 windows on Friday installed on Tuesday on Wednesday they put in a new wet bay done by noon. Since I had the wet bay done the campground was only $10.00 a night instead of $20.00.
I just had one done, All you need is the tank only, do not get the kit for $800.00 the tank cost around $200.00. All you need to do is take off the bracket that the old tank is mounted to turn it around and the new tank mounts to it. Send me a PM with email I send you pictures.
Need 2 days in McMinnville Or. the Evergreen Aviation Museum home of the Spruce Goose and there water park next door can't miss the building there a 747 on the roof where the water slides start. There is a nice campground next door, or stay in there parking lot.
I agree with Ivylog I to would wait to replace the washer/dryer. My wife likes the idea of puting in the clothes turn on and when done there done. No coming back taking out wet clothes and puting into the dryer. We have a 2005 Allegro Bus I will send you a PM.