Yes , agreed a top mounted gear will need some carbon fiber to help distribute the load. The rails do protrude through the fwd and aft firewall but still not a safe bet. I guess I will slide some 1/16" fiber rails and then add some 90 deg brackets to add some additional strength. My opinion is when the CAD program meet Reality Comp ARF had already setup the Jigs. In short, they saw this and let go... I did notice that on their prototype they also made the same cut that your speaking of. Good luck on the rest of your build lets stay in-touch on these....

Phil