This is funny! Happened to me, too. Don't feel too bad Gordon, it happens.
Some of you remember me resurrecting Max Zimmer's widebody Speedster from its wheels-in-the-air-on-jackstands place of shame in the back corner of the garage. Once we got the firing order correct, we rebuilt the carbs, applied my linkage heim-joint fix(not patent-pending) and then synchronized. He said it never ran better. It had a ton of spunk for a 2109(76x94) with twin Weber 40 IDF.
So, what was the source of the firing order problem? It seems our friend Rocky Cimbrec did it to us, reversed 3-4 at the cap. He'd looked at it and was there once when I was scratching my head under Max's rear decklid. I'd LOVE to think it was accidental, but we'll never know! He was quite a kidder, that guy! I miss him.