Really depends on what you are trying to do.. In most cases I'd say just use the generated xdf to compare values with a newer OS that is better supported. If you're just trying to update...

I'm in the same boat, 1999 Silverado with 09373372 PCM trying to switch over to 0411 12212156 PCM. All stock except for a cheap eBay CAI (make sure all the clamps are tight!).

Was getting battery...