I tried this (AEM intake from 4.0 onto a 2.5) and it was a nightmare. I only did it because I got the AEM setup for almost nothing.
The cold air plate fits fine. The bad part is that the intake on the 2.5 is a little further back in the engine compartment than the 4.0, this causes the intake tube to be diagonal across the motor and the filter hits the plate.
I ended up just using the cold air plate, the filter, and cutting the elbow close to the filter to fit my stock tube. When all was said and done, it was not worth the effort.
Sam B.