Resto - 96/97 EXT Triple 600

Hi guys - new to snowmobiling and the AC forum, sorry if this is the wrong place.

Getting a 96 or 97 (built 07/96) AC EXT Triple 600, with FastTrack Long-Travel System, and Extra Travel Tunnel for free from my neighbor.
Looking to see what recommendations on 1) Maintenance to perform, 2) general 2-stroke sled info, and 3) advice on where to purchase/source parts. Goal is to clean it up, get it running correctly and reliably.

Sled has been sitting some years off/on with some light use. Familiar working on boats/cars/trucks and some 2-stroked but brand new to snowmobiles. I was able to find Owners and Service manuals for this year and model.

Any info appreciated, thanks guys. I'll post up some pics soon.