The best advice I can give is to not be afraid to ask for advice on this forum. Spend some time acquainting yourself with the inner workings of the machine by watching the Sawdust Session and reading some threads where others have completely restored machines most would have given up on.
Here is a good starting point:
https://forum.shopsmith.com/viewtopic.php?t=7092
Take lots of pictures and share your journey with us. We all love to watch a guy take one apart, discover what its history has done to it, repair the damages and wear, and then bring it back to life. Besides, pictures you can post of the problems and things you don't understand will help all of us to better help you get your machine back to as good as new, or better!
I just recently got my 2nd Shopsmith for 1/5th of what this one cost me, and it is 34 years younger!! That is another thread:
https://forum.shopsmith.com/viewtopic.php?t=7516
Can't wait to see what you've got and what you do with it.