Tom, I made my bushing 20+ years ago from a 1 1/4 copper pipe and a truck radiator hose, 500 hrs later still going strong. The copper was a little loose on the axel so I spiral cut it and compressed it in my hands till it was snug then greased it up and pressed it into the hose. My 20 year old UHMW bottoms are 1/8 on my 1500A but don't overhang. If your going bigger then Alum bottom I'd do 1/4"
Thanks Glen, just bought a Starduster and thought I'd ski it this winter on the 1500's. Don't think I'll plow the rwy. My Mack isn't running and no way with the ATV.