Richard: I think you have a great idea and would love to see all manufacturers attend and complete with standard spec cars SB or BB.
With all the cars I just wonder how long the comparison or competition will last with one driver. Why not pick 3 or 4 highly qualified drivers who are neutral and ask that they also write down their driving impressions.
I bet MT, Road and Track and others would be interested in covering such an event.
BB and SB run in different classes but certainly their performances can be compared.
Great idea.
Just do it!