there is no date code in the serial numers at all.
welders grabbed droupouts out a big container.
new dropouts were dumped on the old ones in the same container and in that way different serial numbers were mixed and used at the same time.
As you may know all Hutch frame serials are dated.
For exemple 1231707 means that the frame was done on the 12th month (decembre) of 83" n°1707. Same for 0148056 for january 84" n°8056.
That works for all american made F/F.
But that's not correct at all!
I've talked with Rich Hutchins about that!
Serials were only used to keep track of there frames during the production process (chroming, stock, sales).
And i've received several mails from Hutch owners.
They told me when they bought there bike and with serial.
The date code you say, didn't match at all.
I had this info from a famous American BMX collector, so i thought i could trust him, but if you had the info from Rich Hutchins himself, you're the man.
But it should have patterns for the US frames, like 123xxxx and 014xxxx for Pro Racers, 064xxxx for Trick Stars, 065xxxx for Hollywoods, 105xxxx for Judges.
It really seems to me that the third number mean the year.