Apply TCM only tune

[rado15]

Hello all,
I've got a I-1000 (software version 1r04j) and 2015 Silverado 5.3L. I want to only tune the shift firmness with the Firm or Hard profile. I assume that touches only the TCM. I don't want to touch the ECM or other modules because a custom tune has already been applied through another tuner due to physical DOD delete on the engine. Will I be able to do that with the I1000? If so, please provide the steps because I don't want to brick my truck.
Thank you

[mikel]

hmm...not sure here. been a while since I used an i1000 honestly.
Pretty sure its going to force you to select a tune for the engine and trans.