Yep I lived in Dallas for two years and Garland for five and man it ain't just hot, its windy. Lots of hail from hell. Anyway, yes mine has the HUD hole. The pod itself is part of the front upper panel. I didn't keep track of how things came apart really, when I tore it down. Theres three pairs of bolts (IIRC) under that hud front panel, facing down and near the windshield. The airbag HAS to be out, I'm fairly certain. Theres not much wire to work with trying to snake the bomb through the dash pad structure. There are four or six bolts in the area behind the DIC and radio area, a couple are right underneath the pad. Hell, I'm not sure if those had to come out.
It was a seek and destroy type teardown thrash session. The more obvious bolts are behind hush panels, vents, side access panels, instrument bezel, and glovebox. I removed passenger seat, console (bolts under cupholder and bin liner, may be able to leave shift cable attached and set aside though), hush panels, lids on sides of dash, side window vents, glove box, storage bin over fusebox in glovebox, center lower dash cover, dash bezel, cluster, DIC, radio, A/C head.
There was a decent diagram at gmpartsdirect, next to the listing. There is probably an "easy" way. Monday I could get a pic of the 40th's dash so you can see all the attaching points. If all else fails. I just went in with the "look at and figure out" mentality and while no special tools are needed, extra care for blood conservation is a necessity! Its too bad coverlay or just dashes don't seem to have anything for these cars. If you find a cherry one in the boneyard, keep this in mind ... they can be painted. Paint would keep the UV rays from making direct contact with the "upholstery". A few drops of hardener in some plain ol body shop basecoat would be quite durable, rattle can single component stuff might help but not for as long. Just a thought. Holler back if I can help. I plan to drive a drywall screw thru mine if it curls up too bad, lol!
Oh and on RWD GPs... the width between the rear rails is just like the front so if you don't mind a valve cover in the back seat, make a VW Beetle out of it, so to speak. Otherwise, find a storm damaged Camaro and whack it where the rockers meet floor then get-a-weldin! Alas, that thought train ends up at making a V6 Camaro in a very roundabout way. I have thought the options through somewhat and they just fizzle in the light of reality. However, if you did the camaro structure trick (which should be fairly easy) then went ahead and used an LS engine... now that might be worth doing. I been scoping that and I bet it would fit. A guy could rake some coin with that on grudge matches if he kept it quiet... think blown LSX