Trailer Mover?

I have a Power Mover AC10 that I use to move my boat into my garage. It has made my life so much better. I have had it for a few years now. My boat is around 6000lbs and I have to push it up a slight grade up my driveway. I would say that the wheel chair mod could work for a popup on a perfectly flat surface for a little distance. I will tell you, having more wheels will be what you need the most. Also, any type of grade or trying to turn it with that mod will tip the wheel chair over. There is a large amount of force needed when turning a trailer of any weight. Same with trying to get the trailer to move initially - you will most likely spin the tires on whatever surface you are on. My AC10 was made to move 8800lbs and it slips on my driveway and the torque is huge when turning the trailer. Lastly, I would say it will be even harder to get the amount of weight you will need to keep the wheel chair mod using a ball mount. The power mover I have uses a solid attachment and it is mounted as far back on the frame as you can get it - to put more weight on the mover.
http://www.powerdolly.co/products/ac-dollies/