One never knows where Caterpillar equipment might be found. 
Bass Pro Shop - Peoria, Il

These photos taken with my phone, so quality is not the best.

It would appear the D2 in the photo on the description sign is riding on "blocks".
CTS

 

Sheash! look at that corn they harvested back then, lol, looks like a stalk every foot and a half apart, nowadays the stalks are about four inches apart!

CTS might have cowered down and assumed the fetal position, had it been a tailseat J series... har har har. He has a love hate relationship with those "CAT a Paults", rope burn scars on his hands still...
Just poking the bear, I wait by my computer for some snappy comeback from him...
That harvest photo looks like one taken from the D2 R2 archives book. I think the caption said something about seed corn, so maybe it was purposely planted with small plant population?