I had a 75 F250 4X4 Candy Apple red that I bought new for $5400. 360 4spd with granny gear. It didn't have power windows and locks, no carpet but it did have an AM radio and PS and PB. It actually came with split rims. Do you remember those? 10mpg on a good day. That truck was my first...
This is what I made to keep gas cans, chain saw and other stuff from sliding forward in the bed. It's easily removable and didn't cost me anything because I usually have a lot of scrap wood laying around. The pic's were taken when it wasn't completely finished.
I didn't have to do any drilling because the Husky liners use the same holes as the factory liners but I did have to cut it though. The passenger side shock was touching the liner so I trimmed about 1/2 inch off with a tin snips. Very easy install and took me less than a half hour.
I bought my truck off the dealer lot and it didn't have liners. I bought Husky liners. They're a great fit and very easy to install. I can't remember what I payed for them.
My previous truck (Chev 2500 HD) had plastic mirrors and I got some wax or cleaner on them and it looked like what you have on your bumper. I never did get that stain off of the mirrors. I hope you have better luck than I did.
I don't question your post about acoustic glass as I'm not a glass expert by any means. After a trip to Alaska I had my windshield replaced on my 2016 Silverado 2500HD. I asked the guys replacing my windshield if the replacement glass was the sound deadening glass that is original equipment on...