I have built one. I did put the winch on the tractor and built an arch to pull behind it though. The arch doubled as a trailer as the arch part would lay down on the lower frame so I could pin the bed on.
if you are putting the hyd winch on the arch it should work just fine. I would check my hyd output of the tractor with the needs of the winch though. It will most likely be a bit slow.
If you are doing much with the arch on rough terrain, especially pulling downhill, you might consider putting electric brakes on the arch to keep it from pushing you down a hill or jacknifing you. Put the arch fairlead ahead of the tires somewhat to give some of the weight to the tractor. If it is straight above the trailer wheels it will tend to want to tip back and lift the tractor as you get in a hard pull.
One thing more, put a 360 degree swivel on the tongue, you will turn it over and no use in bending metal or breaking a drawbar.
Good luck on your project
