OS upgrade not available 2004 5.3

[D.cooper]

I have a 2007 1500 5.3 with p59, gm gen 3 v8, 4.3l v6 hardware and someone (who I don?t have contact with) already did an OS upgrade before I got to mess with the truck and I can?t change it to a 3 bar OS upgrade now because I don?t have the stock file for this truck to go off of, in the OS area in the VCM Editor it?s just blank. I do, on the other hand have a stock licensed file for a 2003 1500 6.0 with the same exact hardware just different controller numbers. And I also have a stock licensed file for a 2004 GMC Sierra 2500 6.0 with the same hardware but once again different controller numbers and engines and what not...Can I flash one of those stock file?s into this 2007 truck and change the vin back and re do the engine size and stuff So I can do a 3 bar OS upgrade? Once again, all of these files I already have licensed. Thank you!

[2xLS1]

You can't create a VIN/OS mismatch.

[D.cooper]

Okay, so how do I go about doing an os upgrade on something that?s alreasy hade one and I do not have the stock file for?

[* _ *]

license the 2007 1500 5.3 with p59 and compare the p59 to the pcm you'd like the parameters from. Paste those parameters into the p59?

[5FDP]

Okay, so how do I go about doing an os upgrade on something that?s alreasy hade one and I do not have the stock file for?

You don't.

Find another computer is what I'd do.