Soviet Help on army rank, from photo

[Pobeda45]

Hi guys, are there any details (like rank etc) you can tell from this photo? This is my grandfather, circa 1945. He was already 46 by then and had served the entire war as a mortarman, in the 3rd Ukrainian Front. I think he was a private the entire war, but I am curious about the stripe on the collar and anything else you can pick up.

Thanks, George

[ph3s]

In this photo he is wearing 1943 type shoulder-boards, whatever is his rank, will be on them, can you see anything, straps, starts?