84 dropped dead ? Which wire? PLZ HELP ASAP

[nokaoiken]

I helped a friend by changing her water pump and alternator yesterday in her 1984 Tercel. After completing job, none of the lights work and it will not turn over. I checked fuses under hood and 60 amp was blown. Went to AZ and got closest I could get which was 50 amp. Stuck it in and bye bye fuse. This is her only means of transportation and any/all help would be greatly appreciated.

Notes:
1. She drove car to my house to make repairs(lights, motor, etc... worked)
2. I allowed engine to cool and hosed engine compartment with GUNK and flushed with water. I used compressed air on all visible connectors to rid them of any water residue.
Questions:
1. What is the AM 60 amp fuse for?
2. If this is fuse is expired, will this cause loss of electrical power to car?
3. Which wire(s) would cause this fuse to blow?

[KimMG]

It is a main fuse and yes, when it blows there will be a major power failure. Make an enlarged copy of the wiring diagram. Use a highlighter to trace all the affected components. Use the properly rated replacement. Check the wiring to the alternator to make sure it is properly conected. Make sure you have the right alternator for the car. Compare the colors of the wiring to the alternator to the wiring diagram.