Bob,
There's 2 different ways that I clean them. One is the "in-dash" version, the other is the "after I've pulled the dash out of the junkyard" version.
The "in-dash" version: Get a damp cloth to get the dust off, then use ClearGuard protectant. I generally just go over the large flat surface of the upper dash, the glovebox door, and "some" parts of the lower dash & the center console.
The "after I've pulled the dash out of the junkyard" version: (this is ASSUMING that the upper dash is sitting on either my lap or on my workbench). Get a damp cloth to get most of the dirt & dust off. Then I use the ArmorAll CLEANER (NOT the protectant) and start going over all of the large flat surfaces to get the rest of the surface dirt off. Since at the moment, I've only done 9 Black dash pads and 1 Maroon pad (which I've just "barely" started at the moment), for the Black dash pads, I'm using Mothers Back to Black to do the final cleaning & shining on the flat surfaces. I'll also do the same for the instrument cluster hood. At the same time, I'll also unscrew the 2 switches that are on the sides of the cluster hood & clean off the dirt on the switches (or knobs if they are the early 82 - 83 ones).
While I'm cleaning the upper dash surface, I also undo the brass clips that hold in the side window defroster ducts & take them out. I then use a wet paper towel & clean out all of the dust that is inside them, then install them back on the upper dash pad.
At the same time, I'll also unscrew the mounting screws that hold in the main air vents that are on the sides, & the main air vent assembly that is in the center of the dash. I'll then take apart the air vent assemblies & use a wet cloth to get all of the dirt & dust out of everything. Reassemble, then screw them back into the upper dash. After everything has been reassembled, I'll then bubblewrap the whole upper dash & box it & prepare it for shipping.
Now for Scott Hamon's Maroon upper dash pad, I may do things a bit differently. Since I'm not sure how well Mothers Back to Black will work well w/ the Maroon color, I'm not going to go this route after I'm done w/ the initial cleaning w/ the damp cloth & the ArmorAll Cleaner. Since Scott is trying to keep the Maroon color consistant on all his parts, I'm going to use the Meguiars Protectant Wipes on his dash parts (since that's what he's using at the moment), & see if that get's everything clean & shiny. I'll try some Mothers BtB on some other spare Maroon parts that I have & see how it turns out.
I have not had the chance to clean any Blue or Terra Cotta dash pads yet..... Sorry....
Hope this answers a few questions. When the dash pad is still in the car, I don't really do a "super" detailing on my dash, I only do it, if I'm cleaning the dash for someone else that I got the dash pad for.