alternator screw up

[Rammunition360]

so i hooked up my new 60 amp alternator just now, and when i hooked the battery back up something (which i think is a relay) popped real loud and started smoking under the black cover on the passenger fender (83 2.8)...i took the cover off and didnt see anythin melted but i know somethings fubared, what could that be and why?

 

[Rammunition360]

figured it out, nvrmind

 

[metalmacguyver]

Well.... What was it?

 

[Rammunition360]

rusted wire coming off of battery term., i just soldered a new one in