Bulkhead 1, mark II...

As I feared, with many long-term projects, mistakes will not be found until much later and hence no indication as to why or how the mistakes were made.  Applying some experience from a brief stint in shipping, the saying in our dept. went, "It's ok to make mistakes, as long as we catch it."

While laying out parts something didn't look right on bulkhead 1, bottom & side bevels were all backwards.

"Back to the old drawing board."  Bulkhead 1, again.