Thanks so much for your posting. I did check out the Bibliographies at the US Army Military History Institute and found one book that might be helpful as far as the tank units go but could find nothing appropriate for the Coast Artillery in Panama.My problem is that I almost need to know what Army units were in Panama between Jan 1942 and Jan 1944 so I could narrow it down that way.The armored force patch that Dad has doesn't have a numerical designator on it -- it's generic I guess you could say.I do know, however, that while he was in Panama (Jan 1942-Jan 1944) he wore a Coast Artillery lapel pin and also had an Armored Force patch on the left sleeve of his dress uniform; I don't know if he could have been assigned to both at the same time or not.He was actually a communications specialist -- he strung wire from the different jungle outposts to each other and then established and used a switchboard.I've got pictures of him on telephone poles and at a switchboard in a tent.I have not been able to find out what units he was assigned to or where. I have also been unable to find out exactly what Army units were actually in Panama in 1942-1944. I do have his Army autograph book that indicates he was "assigned" to Fort Kobbe right before he came back to the states. I would love to find out what port he came into also.This part of his Army service is pretty much a mystery to me and it's very frustrating especially since I have detailed documentation on his assignments AFTER he left Panama.