You'll be in for a lot disappointment when you plug everything in, expecting everything to work just as you imagined, and come to see so many things going wrong all at once.
Instead, do the install gradually and in small increments.
If your bezel is done--great! Now put the monitor behind it and mount it.
If your PC is getting the proper
power, plug it in with the screen and make sure you can control it (touchscreen/keyboard/etc.)
If your amps are in and powerless, run the appropriate power and speaker wires and make sure your audio is working. You could actually start with the amps because by now you'd probably want to have at least
music in the car (by connecting a regular CD player to the amp).
You're the only Newbie I know with 10,000+ posts.
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