I had a simular problem on my 52' w/ a 235. I ordered a heavy duty rad. It was thicker. Had the short shaft water pump but no go. The fan was scraping the radiator. Wanting to be correct and mount the raditor on the back side (re: engine side) on the core support, I removed the straps that hold the flange brackets to the radiator. These straps are just soldered on and will easily pop off with a few seconds of a MAPP gas torch.
Then once the the straps are off with the flange mounts in tow, you grind off the spot welds to remove the brackets.
Take these to you local weld shop and have them re-spot or other the brackets back on to the rear (engine side) whatever distance you need for clearence. In my case, they just aligned it with the original paint line (about 3/4 inch back). This kept the angle exactly the same as the original. Remember your radiator angles down a bit to stay inline with the angle of your engine. I then re-atteched (soldered) the brackets in their original positions after tinning both the radiator sides (top and bottom) and the insides (contact areas) of the straps that hold the brackets.
One other thing I did, and you may not need to with a 216 water pump, it that I dropped the radiator lower in the Core support to bring the fan blades closer to the center of the radiator.
Now this may sound like a bunch but really, like everything else, it is just a series of steps to achieve a means. One thing i've learned here at this forum and at home is; there is always a way. Thats part of the agoney and the joy of this hobby.
