Headlights, brakelights, heater, and gauges all dead?

My 2 step limit stopped working, it was not getting juice. so I wired it into my gauges hot wire and it worked for all of one second.
now almost the entire car is dead. I replaced 2 20 amp fuses under the dash but they look like they burned out in 1971....checked the headlight fuses on the fender skirt and there ok..

Where should I be looking and why would my 2 step be pulling so much power?
any help would be great..
Thanks again.

car is a 1971 dart.