'57 leak from rear axle

[dickday0]

I will be the first to admit that when it comes to how cars work, I'm dumber than a rock. I do love the Tbirds though.

There is a leak coming from the bottom of the rear axle. Last Fall, when it was up on a lift, the mechanic cleaned it up and said to watch it. Now, the leak has gotten worse.

I've looked at the exploded drawings and see that there is a gasket that goes on the housing and there are seals inside there.

Any idea what I will be looking at when it comes time to fix it?

Thanks!