You seem to be operating in 3's ... Delta Coy goes under support
arms attached. At higher levels, support arms will include signal
plt/coys, MP, med coys, etc ...
By 4 coys, I mean the really old, British Commonwealth derived
Battalions with 4 line infantry coy (+ further support
elements).
The GPMG/s belonged to the Coy but is attached to the
Platoons but I can't remember how many GPMG teams each Coy
had.
3 MG teams per Coy.
The old orbat, as you've mentioned, had all the MGs in an MG
section under HQ, although, as you've also mentioned, operationally
they tended to be parceled out to the platoons anyway. Orbat
different but tactically pretty much the same.
I can't remember how many Sections per Platoon.
I THINK it was 3 Platoons per Coy.
3 Sect per Plt.
3 Plt per Coy
Has never changed. Again, do not get confused by HQ and support
elements. When we mention 3's and main composition, we only talk
about the line units/maneuver elements.
I can't remember how many men per Section.
See if you can recall if there were soldiers carrying M16 and
nothing else (other than SecCom). If there were, than it's 9MS.
This is dependent on your men carrying all their issued weapons
outfield. If someone conveniently "forgot" their LAW tube than
it'll screw up the Picture.
Basically, in a 7MS, other than the SecCom, everybody else is
carrying a support weapon - be it a M203, SAW or LAW.
In a 9MS, besides the SecCom, there are 2 other rifleman (incl 1
SS) who aren't carrying anything else.