Where you work will take backseat to your scores. Put as much effort into your gpa and lsat as you can. Other than that, working in a factory can play to your advantage (in a ps talking about understanding the struggles of the average man/woman, and how it has shown you how to be humble and committed to helping those who struggle), etc.
Don't rely on military history to help that much. For some more liberal schools it could even be a hindrance. Just focus on what your dreams are, and work on the things you have control over (like scores, lors, and your demonstration of comunity service).
Is working in a blue collar job a deterant? Heck no! I worked one for years, and was a stay at home mom for years, and I got into my top choice-the school I've wanted to attend since I was 14.
Best of luck!!