I had a 235 in my '50 3100 using my original 216 short shaft water pump along with the pump relocation plate and the original 216 fan. I had no clearance problems. I've replaced the 235 with a 261 transferring the pre mentioned parts and adding a bolt on the crank for the dampener and again no clearance problems. Are you using your original 216 radiator or a replacement? A replacement might have a thicker core.
