I'm in this exact same boat as you apfelanni. I already have a flat screen monitor mounted in my cab by 1X1 and a sheet of MDF. The 25" TV monitor weights a ton. I'm gonna have to make bigger, stronger, supports along the insides of the cab and probably have to use bolts from the outside to hold the 2X4's in place. It's going to be a project for an already complete cab.