Looks good. I have made 4 similar hitches. 2 of which were from re-purposed truck hitches.
I will offer a few suggestions though, and its up to you wether you do it or not.
1. I would close/weld up the gaps where you bent the channel. Probably not needed for strength since you have the vertical member in the middle, but would make it look much better and less likely to cut yourself or get snagged when hooking/unhooking.
2. I would lower the TL attaching point. Or possibly raise the TL on the tractor side to the top hole. Ideally you want the TL and the lower 3ph arms to be at the same angle (parallel). It looks like your TL is going more downhill than the lower arms. That causes the ball to change angle when raising and lowering. The top hole on the tractor would make it not change as much. But if you had the TL and lower links at the same angle, the hitch would remain perfectly level through out its entire range of travel.:thumbsup: