Welcome to the forum and congrats on your new (to you) tractor!
I'd go over it once with a grease gun and a close eyeball. When sitting for a few years, critters (mice) and bugs like to play with it. Check for wires that have been chewed on, inspect filters, drain hoses and small places for bug nests (particularly mud daubers)
If you have a cab, check the filters and duct work there as well. Hate to turn on the A/C and get blasted with mice poop or bees.