My company is getting rid of (2) Cummins 855 powered generators with less than 500 hours. They are close to 30 years old but are in great shape, have been kept inside and have had impeccable maintenance. I've been looking to see what these engines are valued at but haven't had much luck. One generator is bad and the other is on its way out so I'm only interested in the engines themselves, which run great. Any ideas?