I have a Scotty air unit on my 3500 hauler and am very pleased with it, dropped EGTs about 150°. On my 2500 I don't pull a load much but with my right foot problem I still manage to get the EGTs up there. Since I had the extra air box I decided to experiment. Drilled 2-7/8'' holes in the left rear side of the the air box and another in the Scotty firewall location. 3" is about the largest you can cut on the side of the airbox without hitting the clean side of the filter. Connected the holes together with 2 1/2 shop vac hose, a perfect fit. I am running a K&N filter. Test results-on my "known hill" EGT is down 100°, engine is a bit louder, filter minder didn't move (before it went about half way). Before I could hit about 75 mph before backing off due to high EGT, now 95 with room to spare(ran out of hill). I'm sure that a Scotty unit will flow more air but this is a cheap inbetween, all it cost me was a little time and scrap piece of hose I had laying around.