i hate to say this but i would bet that a lot of them have been cut up and scrapped. tanks are built out of heavy iron and are probably worth more in scrap to some people. most people dont look at the old pieces like us monster truck fans do.
it is called Big Red originally called Mammoth they flipped it over for something to do. They sold it years ago to a guy near Ottawa, Ontario I spoke to him years ago he bought from Arels and made it into a ride truck I have seen pics of it painted green but can't remember the name. I have his info but misplaced it so I'll have to look for it and give him a call. Don/Bandit