CSP tune on an already EFI tuned truck

[rbp4u]

My brother picked up a 08 last week, the truck was tuned with an autocal and EFI from someone else.

I was going to update his single efi tune to a CSP file but wanted to make sure I got the correct os in the truck. I read the file that is in there now and the os is a 11551031. According to tune file depot this is for a 07 manual truck, his is a 08 auto.

Should I re-use this same base file to build my CSP file or should I start with the one that is for a 08 Auto?

[ATPCummins]

The 6.7s pickups are fairly receptive to using different operating systems. If you are uncertain you can use what is already working. The later OSs for that truck ending in "807" or "809" will work fine.

[rbp4u]

Thank you. I appreciate the info.