C30 - Dually Rear End & Wheels?

[ScottN795]

Does anyone have insight regarding the stock rear end / brake drums on a 62 1 ton rear end? Let me explain my question; My 62 C30 1-ton flatbed currently has 16" split rim wheels, and I was going to update to a one piece typical dually wheel. However, I can't get the center of the wheel to go over the brake drum, it lacks about a half inch of clearance to fit. This is only an issue on the back of the truck, the front fits no problem. I now have tried several different 16" and 16.5" wheels we had around our shop, and none of them fit. Every one of them will fit the 14 bolt 1 ton rear end my 74' 1 ton, but no go on the 62'. This is my first real experience with "early" 1 tons and never realized there were different sizes... I called a local truck wrecker and he said I was welcome to come down with a tape to see if anything he has will fit. I was just wondering if anyone has experience with this? Also what is the experience of the group suggest the gear ratio will be? The truck is a 235 / 4 speed. (I thought it was a 261, but was dissapointed when I ran the numbers to find out it's a 235 - although it does run great...)

Thanks in advance,
Scott