Just chiming in here on the wheel width topic - the '51 I recently acquired came along with 7 extra wheels that I removed from a '56 model truck. I had to swap out several of the wheels in order to get road-worthy rubber on the ground. I discovered during this operation that the only wheels out of the group of 13 wheels that I had that would fit on the front axle were the RH-5 wheels. The other wheels were all too wide and contacted the steering knuckle. I'm not 100% sure, but I believe there's 4, possibly 5 different styles of wheels in the group. The RH-5s of course are the only two piece wheels with the others being 3 piece. I didn't try them ALL on the front axle, but none of the ones I did try would fit. These wheels have the small 10-lug pattern and they're 20".
