The 26" radiator in the 22" radiator support shouldn't be a problem at all, although it will depend on your brackets. I have a 26" 3 core Champion radiator that I put in my Duster, which has a 22" radiator support. I just drilled a couple holes and tack welded a couple of backing nuts onto the support, so it almost looks factory.
The 4 core radiator could be an issue though, you won't have a lot of room to work with for the fans. But you're just talking about bolting the Champion shroud onto the Champion radiator right?
Looks like the shroud just bolts to the lip on the edge of the core. There should be holes in that lip already, but in this picture is looks like they just used sheet metal screws...
I have a dual fan set up from a Ford Contour in my car. Fits the 26" radiator like a glove. And the fans are cheap, $100 for a new replacement. I'm told on the "high" setting that they push over 3600cfm.
You can see the kind of room I have here on my Duster. I actually couldn't run the "nose cone" on my March pulley because I didn't have enough clearance. E body may have more room though, so maybe that won't be an issue. You can see in the bottom corner of this picture the lip on the radiator that I'm talking about for mounting the shroud. I bolted a 1/8" by 1.5" aluminum bar to mine to adapt the Contour fans, but I'm thinking you should be able to use the stock holes and just drill a matching set of holes in the shroud.
