My Radiator Won't fit

[Pole Kitty]

Ok, so I bought a new Radiator, one of those 4 row super HD that will cool anything but an reactor, Well it doesn't fit right. The problem is that top brackets are about 1/2" to 3/4" to high to fit flush with the support. I noticed that the spot where the lower brackets sit is raised about that same distance at the bottom of the support. I don't know if that area where the bottom brackets attach is suppose to be raised on a 1968, or is it flat along the rear of the support on the new supports ( I will be getting a new one soon). I measured the new radiator and compared the overall height to the 2 row that I removed and it is about 1/2" differance. I didn't know if the HD radiator supports that I bought from Brothers might be the issue, or the radiator that I got locally. Any help would be greatfull before I start cutting and beating this thing in to position.