If it had that many miles on it and it's ran all that long excessively rich, then it's not good for it at all.
I built my engine last year and the car hasn't been on the road yet, but I sometimes fire it up to test headers/sidepipes or let my buddies listen to it. Sometimes it gets a gassy smell in the
oil from just firing it up and not letting it warm up all the way....so I just go ahead and change the
oil in it even when it wasn't been ran that much. But it hasn't been subjected to 2000 miles of being excessively rich.