I've got a 2010 LMG(5.3 vortec) engine, e38 ecu, bcm, throttle pedal, harness, accessories, sensors, etc. I've already disposed of the 6l80 transmission and transfer case. I'm intending to run an old-school sm-465 manual transmission.

I want to retain variable valve timing, and I want to have a functional speed sensor. I also want to use the body control module for cruise control and smart charging.

Should I work from the stock truck tune, or should I flash a ls3(camaro, manual trans) tune onto the ecm? If I flash a ls3 tune, I'd then need to convert it back to a truck tune to play nice with the truck cam, intake, etc.

The ls3 tune will guarantee better functionality of the manual trans(speed sensor, clutch sensor, etc), but the truck tune will guarantee functionality of the VVT. Further, every component I currently have is from the truck, so I 'm more assured of everything playing nice together.

The gist of my question, are there parameters in the truck and car tunes that cannot be changed back and forth in hptuners? Can I add a manual trans to a truck tune, and it will be as good as if I had started with a LS3? Can I convert a LS3 tune back to a LMG tune, so that all the LMG engine components will play nice?