Howdy Scotty!
Where ya been keepin' yourself? Miss you around here.
My theory about "restored" has always been "to each his own". I have MY definition, but don't see that as THE defined rule. There are different levels of restoration. The Greenies (Deere-oids) have their "EXPO QUALITY" to shoot for (2-Cylinder EXPO allows ONLY the best of the best to show) Fortunatly, the rest of us don't have such a high bar to clear.
My idea of a restoration can be a work in progress. (ie, my 150) It may NEVER be "finished" even though it's done to acceptable standards. There's always room for improvement.
When I go to a show, I expect to see restored tractors in various degrees of "perfection". A quality aftermarket seat cushion is better than a ripped burlap feed bag stretched over an old pillow. It's all about what makes you happy though. Me? I like OEM/NOS parts and not too many aftermarket pieces. The next guy might not even notice the seat cushion.
My 150 is probably 95% complete. (Still looking for (A) an OEM steering wheel, (B) a right fender, (C) Correct "period" MF fender mounted AM/FM radio. The NEXT project, dads Ferguson F-40 will be a long, drawn out affair. It hasn't ran in 10 years, and probably won't roll out of the shop for another 5. It will be PERFECT when it's done. Nothing less will be acceptable. If I'm still up to another after that, I'll be doing my uncles old MF50. The standards won't be nearly as strict with that one.