[PapstDFrisco]

PRI = Primary Manufacturer's Instruction, or something like that.
PRL = Primary Roaming List - not nearly the same thing.
(This is sort of explained on XDA forum.)

I highly suspect that it is not possible.
Otherwise the brain trust around here would have figured this out a long time ago. Since it is what gets hosed when you let the Sprint customizations run and you have to restore an original rom and do the *228 programming to get back on your network. It would be great if there was a backup and restore feature/program for that as it would save much knashing of teeth, headaches and other unmentionables. It would be way cool, speaking from experience (ongoing), if this had been possible - or could be in the future.

I really hope one, or more, of the SW gurus around here will attempt to figure this out.