the 83 should have them as well?
Biggest change is on the RH side the way the power is transmitted to the back end of the combine is different, and improved on the 85. Dedicated fan drive belt and pulley, takes alot of load off the double belt.
If its a really late 85, could be one of the last 125 with the R7 tail end with the improved residue management.
If it isnt return to cylinder, There is a factory cutout for it, IIRC 83 might have it by then, but the early N series you had to fire up the torch.
Should hopefully have the dual ram steer axle, which is nice.
So overall not a ton of differences, but a few.
Our farm purchases a combine soley on its ability to do an excellent job in all of our crops, while being fuel efficient, reliable, ruggedly built, and easy to repair. That is why we choose a Gleaner.