Understanding what I read in my 212HD130

Hello ya'll,
it's my first post on this forum, I'm french and I've got my Music Man amp since only a few months
(i.e. just call me triple newbie)
First I want to thank Steve Kennedy for his great website and forum. Keep up the good work Steve !
I recently opened my 212HD130 to clean it up and to check if everything was alright (I've had some smoke coming out of the amp a few weeks ago, the problem is now solved but now I always worry...).
I noticed many things were written on different parts of the amp but the meaning is not always obvious to me. Below is everything I saw, I hope somebody will help me to understand the most of it and/or these informations will be helpful to anyone.
---
back side :
- chassis no 2475-130 EX (EX stands for export, right ?)
- serial no C007433
right side of the chassis :
- handwritten in red :
4 / / 10-22 AK
left side of chassis :
- on sticker :
476113
inside :
on "motherboard", handwritten in black :
mS
10/11 C
near the speakers, handwritten in red :
104 (maybe 10 4)
near the reverb unit, handwritten in yellow :
RL (signature of the builder I guess)
on each speaker, on a sticker :
476718
---
Now take a look at that :
4 10-22
10/11
10 4
could that mean that my amp was built in october 1974 ?
I know it's silly trying to know when the amp was built but I can't help...
That's all for now.
Thanks for reading, sorry for my poor english, hope you will be able to help me
and last but not least, have fun with your Music Man !!!
Sam - http://www.popachubby.ht.st

Hello again,
I got the answer to one of my questions : as my amp does not have the 12AX7 phase-splitter it was not built in 1974 but after 1976...
Sam - http://www.popachubby.ht.st

Your amp was definitely built in October! <grin>
The YEAR isn't always listed. If your amp has a hole in the chassis where the 12AX7 would have been (but instead, there is a plate covering it) there is still a slight possibility that the amp WAS original manufactured in 1974 (the first year of MM amp production) and was modified after the fact (many amps were). They didn't make this model in 1984 (the last full year Music Man was in business).
The speaker information you want should be stamped on the frame itself and have 5, 6 or 7 digits. This would provide manufacturer and date code.