...........But for the others who did have insigna usually got them sewed on by local vietnamese seamstresses and tailors. So alot of un-standardized things happend..............................
That's the point I was going to make when I read the first post.
Combat troops in Nam (and most certainly other wars as well) didn't really sweat the "small stuff " all that much. In Recon (or the Marines as a whole) we had no officially authorized patch. That said, several teams and/or platoons had unit-specific patched made by the Vietnamese tailor that had a shop on the combat base (see the Dunn's Raiders patch below).
Since these were unofficial and unauthorized, they went wherever we wanted to put them, on a breast pocket, over the pocket, on a sleeve, on the bush cover.....whatever. On one point, Top Tuttle was adament;.if we went off our combat base to the Freedom Hill Exchange, post office, Red Cross, USO, Charlie Med, etc, we could not wear a jungle utility jacket or cover with a patch on it
I never served in an Army combat unit but I suspect the 1st Sgt of a grunt Company, like our Recon 1st Sgt, had other more important things to do like inventorying the gear of KIAs, keeping the troops in ammo, gear, food, etc to go around with a ruler to measure if the unit patch and/or chevrons were sewn on exactly in reg. In a REMF unit, it might have been a different story and the Top Sgt there might have been more anal about it.