Firewall Front Steel Fits Builder Chassis 775X & 776X Use With Floor, 5907-FFS, Driveshaft Cover 5907-DST & 5907-TTA or TTM Transmission Tunnel, Made from 18 gauge Steel. Firewall is 60" Wide x 24" Tall with 22” Wide bellhousing Opening. Includes 12 x 24 Lower Kick Panels