You sure are a craftsman. I bought a similar sled from a farm store. Did not modify it like you. It was not as wide. My sled worked, but was a bit unstable side-to-side with a large bodied deer. Large sticks eventually gouged the bottom. If I need something similar again, I am going with a cart.

I usually hunt farms where 4-wheelers and side-by-sides are used to retrieve game. Sometimes a tractor. I prefer to get the whole carcass out and cut on it while vertical.