O'Neil and Dalphonse stepped it up on Saipan by taking over behind their .50 caliber machine gun that had been taken out by enemy fire. They were machine gunners for the better part of the operation.  With intense fire fights taking place toward the front, the machine gun seemed like the better option over their M1. Below are  two pictures of O'Neil and his Citation. The Citation closing with, "His devotion to duty and coolness under fire were a source of inspiration for those with whom he served". 

 
  Pictured above is O'Neil and next to him is his Citation.  The frame and hand match that of the wounded marine.  O'Neil has a cleft in his chin as does the wounded marine.  O'Neil has a scar on his right cheek which agrees with his injury card and the wounded marine has a gauze pad on his right cheek.  The wound to the right cheek, cleft chin, and the respective heights of the two men put the odds that it is them in the picture. The fact that the injury and picture date line up along with the same division as the photographer also add credence to their claim.
   At 18, I told my father that I was thinking about joining the Marines with my friends. I came up the steps meeting him in the kitchen. He had just gotten home from his store and was straightening up from removing his shoes. The war had ended and it was one option I was considering. College due to a relationship was the other. He nodded and said that we would talk about it after dinner. So after eating, he grabbed his smokes and coffee and on the porch we went.  He told of boot camp, cooking on the ships, training on Maui, and then into Saipan. After he went back in, I sat contemplating and weighing my two paths.  Thankful for his words, I continued on with electronics just as I did a few years earlier with my decision for the High School I attended.
  A Tinian story was of them being heavily shelled late one night.  A shell hit close shaking the ground and O'Neil in his hole.  He realized it hit just beyond him unfortunately where a friend nick named Carpy was.  He said he called out Carpy twice and when nothing came back, he crawled to where his hole was.  He suspected it wasn't going to be good as he got near.  "I got close and said Carpy?  I didn't hear him, so I stuck my hand in.  It was just like warm mush.  I layed there a bit thinking and then thought so he is gone now and crawled back."
Though not on the machine gun, I believe this person was helping them move the heavy machine gun. I explicitly asked Nick who was firing the machine gun and he stated, "Just your father and me."