I'm looking to perform a stock L9H/6l80E swap into a classic car. I believe that I need to install a custom OS into the E38/T43 in order to bypass VATS and maybe for other reasons that I do not understand, as well; the engine trans combo came out of an '09 escalade, and I will keep everything stock for the time being in order to simplify things. I've got the trans, car battery with charger, and wire harness with ECM all hooked up in front of me on the bench. Scan tool is hooked up between the OBDII and the laptop. Version 8 reads everything fine, and Version7.5 scan tool reads everything well. My factory OS for the ECM is 12630501-AA.

Now, I have read through http://download.efilive.com/Tutorial...20Tutorial.pdf (hopefully that turns out to be a hyperlink). In the V7.5 tune tool, I cannot read the ECM in order to get to the subsequent steps of the tutorial. I've got a .ctz stock tune file saved from the Version8 Scan and Tune program, but this file extension is evidently not what the Version7.5 Tune program is looking for.

If possible give me a simplistic answer; in addition, if you all have any tips, pointers, or heads up as to some issues I will be facing, let me know. I've got no idea which types of files are for OS's, tuning, etc. or how to go about any of it.

Thanks!