You popped a brake line. Should be easy to find, there will be a new wet spot somewhere. If it is still braking decent, you probably blew the rear line. If you are unlucky, it will be the line that runs between the fuel tank and the frame.
And to second @mingles, my first, second, and third vehicles were all rust buckets, all leaked like a sieve, and all three I would avoid these days. But there is no argument that I learned so much on those piles that I am not afraid to work on any system in a car. These days though I really...
I have the parts you need. Just cut my tub up for scrap a week ago, but I cannot take it to the scrap yard thanks to the beer virus. Door, most of the rocker, B pillar, etc. Not that far away either, especially not if you are willing to drive to Detroit to bring home a truck!