I applaud your desire with the older machine! Before you start fixing anything, I would give it a good going over and find out everything that it's gonna need first. Make a list and estimate the costs. Then prioritize the repairs. You don't say what year or model you have. Some of the older machines can be hard to find parts for. Be prepared to look for used when you can. Ebay and powersportsnation.com are a couple of resources. There is definitely something wrong in the steering. Jack up the front and start taking things off until you find the problem. I use snowmobile skates to support the machine and roll it around the shop. They also get it up off the ground a bit.
Mine: 2018 Sportsman 850SP - 26" Bear Claw HTRs on OEM steel wheels(I really don't like the Aluminum ones)
Polaris Hand warmers, Mirrors.
Hers: 2019 Sportsman 450. 26" Bear Claw HTRs on Moose 427X Wheels.
2007 Sportsman 500 EFI, Polaris Winch, 25" Bear Claws QSC Clutch Kit, Hand Warmers
2001 Magnum 325 MOSE 12" rear wheel conversion. 25" Sedona Coyote tires
2017 Polaris Ranger 1000XP - Roof and front glass
2018 Kawasaki KLR650
2001 Magnum 325 Warn winch and Moose 60" plow-Sent to Daughter and Son-In-Law since his blew up
SOLD 2004 Sportsman 600 Twin