In trying to narrow it down, I'm thinking 98-99 2500 with 5.9V8 might be the combination, but I'm not sure.

Some times in application notes I see 7500GVW as opposed to 8800GVW.
I take it that is the LD / HD difference.

Yes, it is.

Any brands to steer clear of?

Cardone, Centric, Raybestos, Power Stop, Wagner, Wearever, World Brake Resource ???????
I take it AC Delco, and SSBC are premium $$

I try and stick with Raybestos, Wagner, and AC Delco.

Thank you for your input, one and all.
The front upgrade seems straight forward now... oh, last question on the front;
I take it you have to use the 2500 LD pads with the 2500 LD calipers, on the retain 1500 discs?

And as for the back (that I thought was a single option), actually has two options for us 1500 folks.
I can go from the stock 24mm cyl to the Dodge 2500/3500 27mm cyl, or the GMC 3500 30mm cyl.
Obviously all the bigger Dodge guys are going to be GM cyl (this seems to be where most of the discussion is), but for 1500 folks, is 30mm too bigger jump?

For what little it's worth as I've not tried it myself, I would expect that 30mm would be way too much unless you also swap out the master cylinder. The stock 1500 master cylinder might not leave you enough headroom to safely suffer a single circuit failure, and it would really suck to crash your truck as a result of what seemed like a brake upgrade.

My back is biting at me so I'm not going to stay in the chair long enough to do the math just now. If I don't forget, and no one beats me to it, I'll post up some numbers tomorrow. Right now it's time for a hot shower, the burning of flowers, and communing with my insanely comfy sofa.

Use the 1500 pads. The 2500 pads are taller, and will give you some issues.

From notes I've seen elsewhere, going to the 27mm is a 23% increase in brake force, and the 30mm is 50% increase (though a basic area calculation gives me 27% and 56%).
In all that I've read on this upgrade, there was no mention of a bigger master being required, in fact any commentary on the master was that it was not needed, and that the same master cylinder is used on 1500, 2500, and 3500.

The only issue seemed to be some having lockup problems when unloaded... but most of these seemed to stem from incorrect shoe orientation when assembling, rather than cylinder size.

HeyYou,
So are your brake calipers the 7800 gvwr or the 8800 gvwr calipers? I've got the 8800 gvwr calipers on my truck and they are single caliper.