Did the same,medium sport sled,think I went with the 46"'ers
BTW amazon had the best price I found on em
When you do the install make sure you silicone both sides of the nut and bolt. Your shanty will never leak if the snow or ice melts. I didn't do that on my first shanty and had a leaky tub,but my last 2 have been dry as a bone even with 1 or 2 inches of water on the ice.