Esox,
I am obviously from Jersey, but I wanted to build a shanty as well this year. I scratched this idea because shanties are not legal in jersey and I did'nt want to have to drive an hour or two into NY state every time I wanted to use the shanty, so i bought a portable this year,
However, I thought about the retractable wheel idea and decided that if I ever did build a shanty, That I would spring some money for 4 boat trailer swivel jacks and place one on each corner of the shanty. I figured since they slide over the boat trailer tubes I could somehow fabricate a way for them to bolt on or clamp onto the runners, this way they would swivel up when you wanted to slide the shanty on the ice and also flip them so you can crank the shanty up and down to prevent it from sticking/freezing to the ice. Probably would just have to put small squares of plywood under the wheels. I think it might work well, so maybe you can give it some thought.
John
NJ ICE HUNTER