One of my "imaginary friends" has a John Deere 420C crawler he'd let me have quite reasonably. Needs a bearing in the transmission, but otherwise ready to work. I'm not at all sure I want to tackle that big a job: You have to drop the tracks and pull the final drives and clutch packs to work on the trans. IF (big if...) all it needs is that bearing, I'm sure the part could be found. But by the time I paid him for it, drove 700 miles round trip to go get it, spent the Winter fixing it I'd have $2000 or $2500 in it if everything went smoothly (when's the last time that happened, especially on a 60 or 70 year old bulldozer?) Just can't make it pencil out. I can hire a big dozer and a professional operator for half a day (if that) to do everything I want done around here and it wouldn't come to half of that.