Okay, it is installed with the dash speaker.
The dash speaker does not actually full the hole but I kind of expected this. I am sure I could come up with some kind of a screen/boarder but I did not have anything suitable. Other than that it mounted with the supplied brace and seems to be solid.
The radio was still a tight fit getting into its hole. It was only slightly easier getting in, than getting the GM Radio out. I did go with taking the glovebox out again, like I did when taking the GM Radio out. But once I got it over to the radio hole(s) it fit perfectly.
Hooking up the speaker with the bullet/butt connectors was easy and the wires off the multi-pin connector power wires came down just enough past the A/C control to work with them. I extended them using Bullet/Butt connectors to the fuse box. +12 was connected to a pig tail off the Cig Lighter (was already there from PO) and ACC+ was connected to the radio spade directly on the fuse box. I left the rear speaker wires for the kick panels right behind the ash tray.
The external BT Module wire routed down and towards the driver side where I mounted it on the left side and up on the gas pedal brace. Then the Mic wire followed the radio's power wire path (over the column like other wires) and up the driver side, up to the window. Mic clipped on the on left side of the visor.
After getting it all connected the only post install problem I had was the iPod wire. This wire connected to a multi-pin pigtail female connector on the radio head unit. It seems I did not get completely connected/secured after I taped it up. I am chalking this up as my fault and I be darned if I am going to pull the radio out for this. Saying it is difficult to get a radio out/in a AC C10 truck is an understatement. So passengers (aka daughter) will need to use the AUX to connect to the radio or use my phone to play DJ. I hope to properly test BT hands-free soon but my limited garage test last night seem like it was okay. I do like the radio but I didn't expect it to be like my Bang & Olufsen radio in my 2020 Edge either.
Though I am not sure if I should have gone with the USA-740. Without having my hands on it, I'll never really know. I miss the days when you could go into various stores and just look at a wall of a ton of radios and try them out
Now if my kick panel speakers will ever show up.... though I expect challenges to those too (or at least the driver side install with the Emergency break/high beam access).