Used the acrylic panel and the GTN/GMC trays to align and drill holes for the center stack support angles. This was the second try at these and still didn't quite get it right. The holes to the panel came out fine, but the holes from the trays into the angles are difficult. I drilled them to #8, but the screws didn't sit very flush. Then saw the instructions for the GTN say to use #6 screws. I guess they oversized the holes in the trays. And despite my best effort to have everything clamped up right, the alignment of the holes is not great. I will get some more angle strock and try again.