I shot my mouth of with out understanding the details of that Bannerman advertisement. I thought back then you could buy the cannon for few dollars more than a Krag. So the cannon was $250.00 and no ammo available. It was in a thread that has been closed so I can not fix it anyway. Oh well, it was fun to think about anyway.
I do know a fellow that has his own Sherman tank. It has rubber treads and he does occasionally drive it on the highways. He did alter the main gun for simulated shooting (propane blasts). A few years I asked him if people gave him respect when he drove it, his reply is every one pulls off the road to take pictures.