CCIntrigue
I don't know if you and I have talked (PMd or otherwise) on this subject before or not. It's too bad you could not have used the Hydralift. I realize you said they said your cart was/is too heavy. Our Honda Goldwing is around 900 lbs and the lift zooms it right up to the travel position without issue. But, it may be a bit lighter than your G/C. I did the install of the Hydralift myself and, while it was a chore, it was fun too. But, that's a matter of how one looks at stuff like this.
I've been contacted several times regarding the install of my lift and what to look out for. Angle of approach, coach height when loading and off loading, securing or, "tie down" point location(s) and more all must be taken into consideration prior to turning the first wrench, cutting the first cut, or any other starting point.
I don't know who did your install and while you may know them and their work, it is possible they overlooked some of the "stumbling blocks" that you have run into. I don't know the product "Mighty Hauler" and it's traits and characteristics.
Knowing the Hydralift, it's mounting procedures and attachment points, and, knowing I'd be the one who'd do the lift install, it was one of one of the primary factors in choosing a coach. I had to have good rear frame access. It is not an easy task, to say the least. I do hope you get your issues straightened out. It's nice to have your "toys" or, run-a-round vehicles with you when you arrive at your destination(s).
I also set up our 2011 Honda CR-V to be towed behind the Hydralift. That was a cake walk compared to the setting up of the lift. I did the wiring etc and it wall works great. Again, hope it all works out for you.
Scott