Got Cold Feet before Writing Tune

Good Morning:

I just got cold feet before writing a tune to my E38. Here's the situation:

A. I have a 5.3L LMG engine with transmission from a 2013 Tahoe. I was not able to get the PCM//E38 or BCM from that vehicle.

B. I was able to procure an E38 from a 2015 Chevy Express with a 4.8L. Obviously the VIN and Tune are not what is needed in my 5.3L LMG.

C. I downloaded a Stock tune for a 5.3L 2013 Tahoe (LMG) including the transmission module from the HPTuners Repository which is the same as the target Engine//transmission.

My plan was pretty simple: Flash the Repository tune for the Stock 5.3L onto my existing E38 (from the 4.8L) and then install that E38 on the 5.3L. Before launching, I started reading through the VCM Editor forum and I got cold feet. Some of the relevant posts seem to indicated that I could have a problem creating a 3rd set of VIN//OS pairs which would require more credits to flash. Also, some of the posts suggested that I could have a problem doing a Write Entire to a PCM that was not from the original vehicle/engine combination.

So, before I did anything stupid I wanted to check with any//all of you guys to see if my original plan is sound. In other words can I flash a complete tune from the Repository onto an E38 that was NOT associated with the engine on which it will be used? (My E38 is from a Chevy Express with a 4.8L. The target engine is the 5.3L. The Repository Tune is from a Stock 5.3L). Are there any pitfalls that I might run into? And, finally what are the steps I need to take?

Thank you,

Chuck R

bad plan.

Have the ecm flashed to the vin/os pair you want via tech 2, then read with our software & tune away using the file you read.

Flashing your ecm with a file from the repository is a bad idea and not recommended.