I have a rather serious brake fluid leak. About 6 oz per mile!!

From on top everything is pristine and there absolutely no sign of a leak. So I crawl underneath, remove the tray and the steering box is absolutely soaked. The tray has fluid on it and it has obviously been dripping off the tray as I drive. So it looks like something above the steering box is leaking. (Hmm. it may be "spurting" from somewhere else - lot of stuff coming out from somewhere!!)

Question is Where the heck is it coming from and how do I get at it to repair it?