Welcome to Tractorforum Steve,
Great tractor you have there. If I were you I would keep it original.
I agree, sounds like you need a bush hog. If you do decide you need a finish mower I strongly recommend a three point hitch, as oppose to belly mower, much easier to change from one implement to another. Also a rear discharge, that way you can mow “close up” on either side.
I strongly recommend that you use a overrunning clutch with a bush hog or finish mower. This is also known as ORC. A ORC will go on the pto shaft of your tractor and then the pto shaft from the bush hog or finish mower will attach to it. A ORC will keep the momentum of the spinning blades on the mowers from pushing you and your tractor into your wife’s car or her favorite flower bed, even though you’ve disengaged the clutch and applied the brakes with all your might. (This kind of thing will cause you to find out what a real battle ax looks like in action. Don’t ask me how I know.)
I grew up on a 8n. Used one a lots bush hogging with no ORC. Don’t think my Dad knew about them. Probably couldn’t have afforded one if he had. Back then cow lot fences weren’t too expensive to rebuild so ORCs would have been low priority. Besides, small boys on tractors needed to learn to plan their stops.
You might want to get some stabilizer bars to keep those mowers, attached to that well planed out three point hitch, mowing exactly where you want them to mow.
If you know what I’m taking about, forgive me for rambling on. If you need more info post back, someone with more knowledge than I will be glad to answer all your questions. I might even come up with another opinion.
Enjoy your tractor, the 8n is wonderful piece of machinery.