I believe, that for some reason, there is a difference in the mounts which attach the radiator support to the front crossmember between the the half ton, and the 3/4 ton and the 1 ton. It is an easy work around in your case with your "project" truck, as the only thing you need to do is drill a couple of holes in the crosmember to make a half ton support fit.
The half ton takes two bolts while the 3/4 and 1 ton only has one center bolt.
All of this information is available by accessing the deepest recesses of my progressively deteriorating, feeble brain, and subject to being completely wrong, yet I stand firmly behind it and will defend it fervently... Where did my danged glasses go off to now?!
Stand by. My wife is yelling at me some more.
