There's a Cletrac EG on e-bay that looks like someone adapted wheels and tires to it after their tracks wore out. Looks like who ever did it was pretty handy, and put quite a lot of time and thought into it. It caught my eye, thought some folks here might like to see it too. Here's the link : //http://cgi.ebay.com/Antique-Cletrac-Tractor_W0QQitemZ110281483515QQihZ001QQcategoryZ11757QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
If that doesn't work, it's auction number : 110281483515
Wow, that's kinda cool. I'm thinking it came from the factory that way.
The front wheels look like the same ones that are on my ford 841 elenco 4WD. which has a dodge powerwagon rear.