help me decode my 3rd gen hemi

john just about nailed it. With the exception of egr and compression. Compressionn was the same for a ca motor vs the others. And egr is not required on 2500 and 3500 motors. But all 04 and 05 1500 had egr. The 03 did not.

honestly all you need to know is a few things
1 car or truck motor
2 03-05 or 06-08 (determines non mds vs mds)

as any non mds pcm will run any 03-05 motor and the mds pcm will run the 06-08. Then there is the car vs truck and you will need the matching pcm there too. Of the truck pcm's the best are 05 then 04 and avoid the 03. Because of tuning options via diablo. If you plan a stock motor swap then pcm choice does not matter. But if you plan on cam heads stroker or boost it becomes more critical. The cavat to this is if you plan on not using the truck trans. Then the 04 and 05 pcm's are equal. Since the diablo engine tuning is the same the 05 added in trans control for the 05 and up. When it comes to the car pcm I have no clue what one is best.