I'll be doing some land plane work making and maintaining pasture roads and figured a nice crown could be made with an angle. A hydraulic cylinder would be easier than manually adjusting back and forth.

I just wonder about how durable this is and would it last for work when I wouldn't need it (which is most of the time).

I have a Case 480D Loader/Landscaper with a large box blade and scarifier on it. It's basically a heavy duty three point. That is exactly how they raise and lower the right arm…. With a large hydraulic cylinder. I use it for just that… crowning or making the bar ditch.
I think your idea would work great.

I don't see why it wouldn't work. Has to be easier than hand cranking the angle adjustment threaded rod link on my tractor. Hydraulic cylinders are plenty tough.

That's for sure. I've been thinking of doing the center link on my JD as well.

When I was in high schoolI worked for a peanut farmer in Pearsall and they had those hitches on all their tractors. No problems at all.

My peanut farming grandfather had these on his tractors when needed.

However, he put on his hay fork with one of these cylinders on and magnetic spacers were off. Brought a round bale through the back glass of his JD 4040

Isn't it just a "Top and Tilt" kit. Do a search using that. Lots of them out there.

Yep. Top and tilt.

Thanks - that's exactly what I need. But I cannot find a Top and Tilt kit large enough for the Kubota M7 (170hp). I'm guessing this is only for smaller tractors?

Try this place: www. Agristoreusa.com. They have Cat 3 hydraulic top links ( what your tractor needs I think) and various Cat 3 Hydraulic side links depending on your pin sizes and throw dimensions.
You will have to buy them separately and they have hose kits.
I have bought some things from them and have been happy.