[Focus man. Focus.]

We are doing some work in our upstairs bathroom and I have come across something I have never seen before. Our house was built in the 60's and aparently this wasn't uncommon back then.

I took the light fixture off the wall above the mirror. It was mounted directly to the wall, not the box. There were only 2 wires, one white and one black. So far I am good. Now is where I am lost. Instead of having a round box in the wall there in a rectangle box, like a single switch box on its side. Can a new fixture be mounted to this box or will I need to replace the box with a round style box so the fixture can be mounted to it?

I will see if the wife can snap a picture of it and post it up for me.

Thanks in advance.