Better check the serial number on the engine. I'm guessing by the looks of the black paint, that it is an 8-hp replacement Kohler, instead of the 7-hp engine that came in it originally. I'm not sure that the 7-hp engine was offered from Kohler as a replacement very long after these tractors were produced, so every one I've ever seen with black paint was an 8-hp. Not a big deal, you just want to make sure you're following the correct specs when you start working on the engine.
If it were me, I'd try to at least get the engine to fire, so you can find out what condition the engine is in. After that, I think I'd strip that one down and go through it. The tractor looks to be in really good overall condition, but with the years of sitting outside, you'll really need to take everything apart, grind off the rust, lubricate it good, and put it back together. Having done this a piece at a time, I can tell you that it's almost easier to just disassemble the whole thing down to the frame and put it back together. Besides, you can have that one down to the frame in about an hour with an impact wrench and a couple of sockets. Don't bother trying to take the dash tower off, as there's really no benefit to removing it, but everything comes apart pretty easy.