I am wanting to swap my 8l90 in my 2017 Silverado to a 10l90 due to it loosing reverse and gears 4 through 8. I already have an unlocked T87A. I can get the transmission used pretty cheap but they want a killing for the TCM. $3000.00 for it and the harness. They say it is because they are buying a tcm proigraming it and making the harness. Wanted a Stock tune for this trans if anyone has it. Thanks