Adaptive Learning suggested methods within the EFI Live Scan 7.5 Software.

Do these steps with Engine running:
Step 1 > Open EFILive Scan V7.5
Step 2 > Click the DVT Tab
Step 3 > Select Target Controller, in this case, we are dealing with a T43 6-Speed TCM
Step 4 > Connect to Vehicle by selecting Green Radio Button below the File Menu, or hitting Ctrl+F3
Step 5 > Select Activate Control Panel
Step 6 > Select Fast Reset, wait 5 seconds
Step 7 > Select Adapts Reset, wait 5 seconds
Step 8 > Select Adapts Preset wait 5 seconds
Note: (You can stop here and skip to step 11 if you wish...)
Step 9 > Select Fast Learn
Note: Once you hit Fast Learn, put foot on brake, shift directly in to drive, do not let off of brake, vehicle will raise idle, and you will feel the vehicle shift multiple times, process takes approx 2-3 minutes, vehicle will return to idle, and wait approx 1 min at idle before continuing on to next step.
Step 10 > Put Vehicle in to Park, do not shut off yet.
Step 11 > Deactivate Control Panel in EFILive V7.5 Scan
Step 12 > Disconnect controller by hitting the Disconnect from vehicle radio button under the Edit Menu right next to the Connect radio button in step 4.
Step 13 > Turn Vehicle off, and let sit completely off, no accessory, nothing, OFF, for 3-5 minutes. This allows the TCM to completely power down and return to normal running mode.
Note: Not doing Step 13 has left some people without any gears because TCM is still in learn/program mode.
Step 14 > Start Vehicle and see if you have normal driving mode.

Congratulations, you have just completed the Adaptive Learn/Relearn process that you GM dealer will charge you when replacing or flashing your TCM/Transmission.