Another "Hot" problem

I was running an unsealed hoodscoop, on the hiway it would heat up, air was pressuring the engine compartment, and not letting air flow in through the rad.
Can I squeeze a 26" radiator in without to much trouble? I can borrow a 26" and want to experiment with it before I go shopping. I figure 26" is better than 22" if it isn't to much hassle to get to fit. Any ideas or thoughts? Thanks again.