THAT is the point all right!!! Given virtually no rules, no sanctioning body, no class specifications it is extremely difficult to draw any real world comparisons to other replicas.
Perhaps the NASA unlimited class might be appropriate? Even though it says "Unlimited" there are still plenty or "rules" to determine your actual class within a class. For instance, wings and aero devices will cost you points. Certain engine mods as well. There are also tire restrictions and the list goes on. This is to get to a reasonable base line comparison between cars, to level the playing field if you would, even in the "unlimited" class!!
Again the local Auto Cross here, I witnessed with my own eyes. A private owned and prepared FFR Mark 1, bought used by the current owner, who added IRS and a well built 351 with a carb (NOT a Roush) and DOT tires and monster brakes went FASTER THAN a Lola like this one pictured below: The Lotus 7 with a GM V8 beat both of them. He has substantially less than $55K invested in the FFR!!
