You may want to contact the Inliners website and ask around over there. A lot of those guys are into street rods, racing etc. and often have a better handle on things like this than we do. A word of caution however is to be careful of the linkage/firewall clearance problems so often encountered with 3-6 cab setups.
Also try Larrowe & Sons near Sandy, (Portland) OR @ 503-668-0352. Good Luck.
