Scary Larry can be bought from Xtreme Truck 269-278-3906 or HTS Transmission 616-897-6237. HTS may no longer be handling this download however,... I think I read that. I bought mine from HTS.
Xtreme is the Keeper of the Program. I belive the guy who I was told to talk with was Nathan,... not real sure about that.
They will tell you it will work on the 04. 5. It may and they may be right. It didn't work on mine worth a c... p! That was however probably my own fault as I messed with tooooooo many downloaders and I feel they started picking up with residual junk left in my ECM so then none of them worked well. I just had mine reflashed and it was a world of difference and I loaded SMARTY on it as it is the best I've found for all around performance and driveability.
For KILL mode however, from what I know about the Scarry Larry,... then it is probably the man,. . for right now. It will cost you $50 if you have a Triple Dog already. Only the Triple Dog will it work on, fyi. From the numbers posted on TDR/DTR then Scarry Larry has to be around a 100hp more than anything else. You absolutely must be billet throughout on an auto however and you'll need an upgraded turbo and probably head bolts. You play you pay,... right.
Reader's Digest Version,... IMHO you can't mix this or other downloaders with the SMARTY. For myself that is why I'm buying another ECM for everything else for when I want to use it for drags or events. These downloaders WILL corrupt each other to a degree. The purer you can keep it the better your truck will run or have the ability to get the truck reflashed b-4 you load another loader,... especially a SMARTY. That does not mean there is a problem with the SMARTY,... it means it is MORE sophisticated than all the others and it does not play well with others. These are my opinions based on what I have seen on my own truck. So you can learn my other's mistakes or make them yourself. Enjoy.