Marc,
Don't want to discourage you from that Kato but do not want to take advantage of your in-experience. I would not buy it personally for $20.00. Don't get me wrong, it is a very nice running engine as are all Katos but the appearance is all off. These older Kato GP-9's were made considerably "oversized" for some reason and have a large gap between the trucks and the end of the engine that makes it look odd, at least to me. Apparently to lots of others also as N Scale of Nevada produced a whole new frame for these engines to correct the appearance. Even at that, once the corrected frame is installed they are still oversized when compared to the later releases.
Thanks for the big boost in price and by all means continue on if you want it. I just wanted you to know what you would be getting.
prof