So far, this is how the numbering system is shaking out:
First serial numbers were four place digits. I have 0326, so there is a 0001 out there, possibly a 0000, and a 9999.
Serials up to 17693 were produced in 1977.
Serial numbers 17694 - 334585 were produced in 1978 when 316,892 LB7's were made.
Serial numbers 334586 - 785250 were produced in 1979 when 450,665 LB7's were made.
Highest all numeric would be six places, 999999. I have recorded serial number 914569. Thus the first million knives had no alphas. This point was reached some time in 1980. A total of 1,106,906 LB7's had been produced by the end of that year.
When the single alphas were added, the serials still kept to six places max, so only 99,999 knives were made of each alpha. Lowest alpha recorded so far is A25594.
When the rotation went to double alphas, the serials went to seven places. I've recorded BB56630 as the highest double alpha. Some time after this, the serialization ended.
This is what I have so far.