Hi Marion, just wanted to update this a bit. I finally heard back from my Uncle, seems he was in Bougainville. I've come across some good stuff on the invasion there just haven't had much of chance to sift thru it yet. He sent me an accomodation that his unit (actually the whole 3rd Marine Division) received for their actions there. He was part of the Naval Construction Battalion, First Marine Amphibious Corps. Tried to do a cursory search for some information on that but came up with nothing.
He also sent me some information on his half-brother who was a ambulance driver and received the Bronze Star for his actions at Okinawa & the Ryukyu Islands. Pretty good stuff there.
As I find out more or if I find out more, I'll keep this updated. Thanks again for your help Marion.