Ahhhh, thanks! I'll look into that.
is that what I have? The pcm555s?

What engine do you have???
454/502mpi/500efi use MEFI's
496HO/525EFI/700SCI use PCM555

2002 6.2mx

MX should be MEFI 3.

Really not much there just changing the ECM tune on the 6.2

If you have stock OEM exhaust - just adding that the exhaust risers for the 6.2 / actually all V - 8 smallblocks are the exact same as the 4.3L - 190 hp V - 6 - 3bbl carb app. Very restricted on the exhaust side for a 377 CID. The OEM manifolds are poor as well but the risers are joke for making any power.

All Rinda / Diacom are just scan tools - they DO NOT offer any form of recal for the ECM nor any PCM's.

I just put on all new aluminum manifolds, spacers, and risers. Mind you, this fat pig is 12500 so every bit counts.
As for the tuning bit.. Being the gear head I am, I foresee twin turbos on each engine in the near future. Once I do that, I'll be better off going megasquirt, holley, etc dfi. All gm based. I can't see paying 2k for just software, that's insane.