We are cleaning out my grandparents barn and came acrossed this old cat d4 crawler. I want to know more about it. Does anybody know where we can find info on this? And maybe what year it is. We think it is early 40"s but that is just going on some pictures that we saw of other crawlers. Also we are going to try to sell it for parts....I know it isn"t much but we thought maybe somebody could use it instead of us scraping it.