What Mark-Ia calls a "loop style" were also called a "twisted clevis"; the clevis is attached to the tractor drawbar with a hitch pin, then the clevis turns 90 degrees so it is horizontal, then you just drop the "jaw" of the hitch into that horizontal loop.
That clevis is for trailer plows that have the rear wheel on the ground at all times. The older plows have the whole rear end of the plow raise up, even the rear wheel is in the air when not plowing. Those hitches often need a different clevis.
As for that trip rope; DO NOT tie it securely to the tractor seat with a stout rope, use some twine or rope just strong enough to trip the plow. If you hit a rock or root, you want the rope to break off because that spring hitch will allow the plow to stop right now to save damaging the moldboard while your tractor is still powering forward....trust me on this!
Best is to tie on with a homemade wire clip that will give way easily. Just give the rope a quick jerk to raise or lower the plow....don't pull and hold it as then the plow just keeps going up and down. All this has to be done while the plow is moving foreard.
LA in WI