Century Arms L1a1 Serial Numbers

CENTURY L1A1, FAL RECEIVER CODES
i have been using century receivers for many years and finding out information on a particular receiver is difficult at best.
i have collected some information on the receivers and it may or may not be correct.
this is not going to be in any order, it is just information.
If anyone has addition information please post it.
this thread is not 'I repeat it is not for the bashing or merits of the Century receiver' it is only to gather information.
if you feel the need to do some bashing, then feel free to start your own thread.
if it stamped 'made in canada' then it is most likely an Imbel receiver, but there were a few Argentine (FMAP) receivers used (5 digit serial number ).
Hesse/Vulcan made some receivers for Century and they are usually stamped with Hesse on them, altho a few were not stamped. type 3
imbel also made some receivers that were stamped Imbel , but without the gear logo on them. type 3
Imbel made some receivers with the gear logo on them. type 3
the early L1A1 receivers were Imbel metric receivers, but cut for the folding charging handle and had the unibrow cut. type 3
NC on the serial number are made by North Country Machine in Vermont. i have only seen metric receivers, type 3. but, i read there are some inch made, but i don't know for sure.
ICL on the serial number are early Dan Coonan. ( i think i remember FAC may have had something to do with them) they have the unibrow ramp and are cut for the folding charging handle. the were cut for the inch mags. inch receivers. they are type 1
CA on the serial number are ( i forgot i will add this information when i remember it.) they were metric receivers. type 3
CI on the serial number are thought to be imbel. metric receivers type 3
PAC (?) made a few receivers for century and are Imbel receivers. metric receivers, type 3
century bought out FAC (?) inventory when they went bankrupt, there were some receivers in the inventory. i don't remember which rifle they were used on (metric or inch).
some receivers are marked R1A1 ( metric) type 3
some receivers are marked L1A1 (inch) type 3 and type 1
receiver tap for barrel= 1' x 16 tpi
receiver gas tube tap= 9/16 x 24 tpi
please remember that this is an old man trying to remember stuff or looking at random notes before it is all gone from his mind.
if i remember more i will add it and if i remember something different i will correct it.
if someone adds a correction i will correct it.
i am just tired of spending time hunting for data that i use to know.
ron