I also use the 2x4s fastened together with eye bolts with the wire fence in between.
On the other hand, I don't hook it to the tractor, because its not heavy enough. When I'm cranking it tight, the tractor moves too. That does make it harder to tighten because I have to use some other post as the anchor, and there is not always one available. If it is on a straight section, there is no problem as I mount the fence to the one end (post) and tighten the other end of the wire fence(in the middle of the line of fence posts). Otherwise if I am at the other end (short fence) or going around a corner, I might not have a good anchor.
I tried using my wife's Silverado once, parked sideways, and it still moved the truck. And she doesn't like her baby out in the field.
Pete