<div style="margin: 0in 0in 0pt"><span style="font-size: 9pt">I won't use anything other than birch core Dragon Plate. The stuff is ridiculously stiff. I just used it in a build for a Q80 and I have more cutouts than carbon. I used 1/8 inch, but for a firewall as big as yours I might go with 5/32 or 3/16. The &frac14; inch stuff works great in reinforcing your house foundation!</span></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><span style="font-size: 9pt">http://www.dragonplate.com/ecart/categories.asp?cID=3</span></div>