I'd never make any money, I'm way too picky and would spend too much time on each project LOL.
You could tune Gen 3 Hemis. My 2009 had a built motor, blower, etc and was tooooned. Had to use Diablo which was bumpy but it worked.
Yes and no.
Somewhere in there they locked them down.
My 2013 Ram was not able to be tuned. Same with a bunch of guys who wanted to prochargers, whipples etc.
Even when the Hellcat launched, there was a video of SRT engineers talking about how they were shocked no one had made 1000hp with a Hellcat engine yet.
It wasn't like GM or Ford who seemed to use a 1 digit PIN to unlock their ECUs. Even now, you either send in the ECU to be unlocked or buy an unlocked one.