Wow, what I see there looks really cool!
Its a nice kit, I look at John Ps and think about how I'd like to do mine.
Surely a man of your skill could cut an airbrake from sheet? its only a couple of flat shapes.
Look on the bright side, I am still working on my Keaton batmobile cos my dog chewed up several parts, and after I re made them, he chewed those too! I am on round 3 now.
Cheers