I am in the process of building a FIA/NASA approved roll cage in a 2005 Ford GT and the rules don't address attachment strategies/requirements for attachment of the mounting points to the aluminum structures. The rules provide guidance for mounting plates (0.120" thickness minimum) size and how they are welded/bolted to steel floors/sills but in this case, I'll have to either add alum "bolt to" plates, reinforcing plates, and/or backup plates to the structure. Wondering if anyone has explorer/researched this and what their findings were. Yes, I have the rule books and I can "interpret" intent but input would be appreciated. I have the MaTech GT build photos/specs and insight on how they did it..... but I can see it would not meet NASA minimum standards (e.g. 18 in2 minimum size for mounting plate area on floor corners).