The block serial number should be stamped on the bottom back of the block on the pan rail, just outside the
oil pan flange. I don't know if Shelby keeps track of them, but I have been curious too. You might try to reach Mike Lefevers at Shelby in Torrance if he's still around. He balanced and assembled my rotating assembly. Been there forever.
Optimistic dyno numbers? People do that???
I have an old dyno sheet that put mine at 558 lb tq and 497 hp @ 4500 rpm. It's an old dyno run and I have since changed carbs and some other things, as I believe it should be posting higher HP numbers.
Going to look into changing my exhaust and do a chassis dyno in the near future.
I have the specs on the build as it sits right now somewhere if you can use any of it for reference on your build. I will try to find it and send you a PM.
I would be curious what your software says about my build too....