1989 Olds 88 Royale Electric Short

[rusted and busted]

Last week i accidentally dropped a screw into the cigerette lighter and blew the fuse. Unfortunately when this happened the fuse didn't pop immediately and the lighter was sparking for a few seconds. When I replaced the fuse it looked like the plastic had started to melt. I placed a new fuse in the fuse box and it popped. I then checked the circuit and it is now grounded. I disconnected the lighter and radio wires by the lighter and it didn't make any difference. Besides the radio and lighter not working the horn and heater/AC doesnt work either and the tripometer clears after the car is shut off and the clock/calender also clears after it's shut off. I should mention that the car has the digital dash board but everything works fine there. I'm not to good at tracing down a short and was hoping someone on here might have an idea.