Here's my experience with the aftermarket dashes -
1. That giant blob of uerethane is terrible. It's a bad idea that they never should have developed and sold. It's very heavy, and it sags in places it's supposed to be straight.
2. Whatever dash you end up ordering, make sure it has a metal underside just like the factory dash did. I bought an aftermarket dash off Classic Chevy Truck parts, and it's wavy all across the back. No real way of fixing it, without leaving heavy weights on the dash in the summer. And just hoping that it doesn't screw something up. I mean maybe you could get some 1/8" flatstock steel and glue it all across the back of the dash, where the windshield meets the dash. But you'd be better served to avoid all this and just get one that uses metal. Plastic ain't going to work for this task, but of course they tried anyway.
3. That coverlay dash cover seems to work ok, but makes the dash look notably thicker and just... bigger than a stock dash. I'd stay away from it if you don't want your truck to look a bit odd.
I may be wrong about this, but I think that LMC sells a viny dash with a metal underside. It looked that way one a video I saw of someone installing it. I'll probably try that one next after I call and verify it's metal.