I have recently bought a old OC-3 crawler loader from a gentleman for $500 dollars. It has not ran in at least 20 years because the tree I had to cut to pull it out had at least that many rings. I am now in the process of getting it to start, and repairing needed parts. The serial number on the plate reads 10wh-144. Can anybody help me with these numbers, as to the year so that I am sure when I research parts?