DeWitts "Direct Fit" seems too thick to fit- what am I missing?

[billschroeder5842]

I need some advise please....I'm in the middle of the project so I'm putting this up on both CF and ZR1Net...

I'm installing (or trying to) a DeWitts "Direct fit " #32-1139090M in my '91 ZR1.

Removal of the old radiator (a stock style) was pretty straight forward. I'm putting back together and is simply is not. It looks like the radiator core is too thick from the stock (about 1/2 inch more) and the fan shroud that holds the electric fan it hitting up against the core. The fan shroud has these "Squarish Blisters" that protrude as some sort of mounting surface and hit the core, not allowing the fan shroud to close against the fan mounts. The gap at the junction point at top is about 1/2 to 3/4 of a inch and is uniform across the back, so everything seems to be aligned correctly albeit too wide.

So, did I miss something on installation, is this the correct radiator or is there some modification that I'm not aware of?

Any ideas are appreciated