Interviewing for Management Level Position at Plant-Type Facility (Updated OP)

Ok, I'm going to be interviewing for a position at an industrial facility.

I'm an engineer, an the position will be management level at the facility.

My question is: What do I wear??

My current job is at the corporate level, and the interview was conducted at the corporate office where I work. It was a no-brainier, I wore a suit and tie. Every other job I've ever interviewed for was consulting-type engineering and in a strict office setting. So again, suit and tie.

This is not to say there's not an office on site where the interview will be conducted, obviously, I just don't want to seem way out of place if I show up in a suit.

I don't want to over-dress and I don't want to under dress. Anyone with any recommendations??

UPDATE BELOW:

I was going to wear my suit, but I left the jacket in my car. I didnt have the jacket on when I arrived. I had to check-in with security office. So, after I checked-in with the guards, the plant manager came to escort me to the offices. I just decided not to even worry about putting on the jacket. Fit in just fine. I think it would've worked either way, though.

I have a second interview scheduled now, at the corporate office. Exciting times.