To my knowledge the 45 degree tires were the only ones available. 

We picked this tractor off the "showroom floor" in Kankakee IL. Whatever it has on there is the way it came from the factory. The only thing any different is the rear circle weights. I think the 1206 was the start of the IH split weights. We had quite a few of the IH circles that fit everything IH ever made. So, we bought it with no rear weights and bolted our own 145 # IH weights on. 

We bought it without duals because the salesman said with these BIG tires, duals weren't needed. A year later we added duals. Probably wishful thinking on his part. Later we also added the screened intake pre-cleaner to replace the IH "tophat". We only had one SCV circuit on it also, so only 1 stick in the cab along the seat.

Another big deal was breaking in the engine. When they delivered it the IH mechanic said to let it run all night in the shed & he'd be out the next day to pull the valve cover & reset the valves. So, that's what we did.