The panel frames are .125 2024-T3 aluminum, with some lateral and vertical .063 angle on the back, to stiffen it up, and facilitate the attachment of radio trays, wiring clamps, etc. The Skyview system is great, but keep in mind that it isn't the only one out there. Play with them all and see which one you like. I highly recommend the GRT Sport.
I currently have another dual display GRT system going in another Long-EZ, and have an RV-8 that will be getting a dual Skyview system this summer. Besides the 10" Skyview in the Long-EZ that you see here, I've also done a 7" in a Wheeler Express.
Where are you located?