I agree with you as to the extent of the restorations out there. The 990 Oliver is my favorite and I really pick them over when checking them out at auctions and shows. I also personally put a high value on farm fresh tractors that have been taken care of their entire life.
I notice you have the optional seat back on your rig. Did you have to hunt that down or did it come with the tractor? I just can't seem to find one anywhere. I am also looking for a belt pulley attachment for the pto.