not sure, think they quit trackmasters in 63 when they came out with sprytes in 64???Not mine.
1969 Thiokol Snow Cat - atvs, utvs, snowmobiles - by owner - vehicle...
1969 Thiokol Snow Cat $25,000 obo When we bought this thing a few year ago it had to be drug off the trailer. Since then, about $3,000 worth of parts have been put in it and hundreds of hours of...butte.craigslist.org
Defiantly a 603, I had one. Good machine, has OC15 diff.. Downside is unless you are in Antartica, you had to have the doors open all the time or you couldn't take the heat.That's a 603, not a Trackmaster. Was posted on FB Marketplace a week or so ago:
1969 Thiokol 603
Just chanced across this on Facebook Marketplace. Not mine, no affiliation. https://www.facebook.com/marketplace/item/585926329321081/?ref=search&referral_code=marketplace_search&referral_story_type=postwww.forumsforums.com