Newbie here. I am sure there is a link somewhere but..

How can I put the DTC's from V2 into a file on the computer so I can post it?

I know, for example have 6 codes I need to address.

One is the back up tail lights which are on a manual switch not via the ECM, so I need to turn this system off. P0650

Another easy one is the Vintage Air conditioning clutch relay control circuit which is not operated by the ECM, its just manual, again, need to turn this off.
P0645 air

TCM is throwing P0787, shift timing solenoid low. Could this be due to my mods on the tach output?

P0050 O2s Heater control circuit bank two sensor 1

P0171 Fuel trim system lean bank 1
P0174 Fuel trim system lean bank 2

Some of this due to my inability to calibrate the o2 sensors??

Thanks guys. ANY help appreciated.