Nissan Repair: Where is the main fuse/breaker?, fusible links, beering

Question
I recently replaced my alternator on my 89' nissan 4 cyl. pickup
because of a seized beering. In the process I accidently shorted out
the battery. I completed installation and all is good except for no
power at all to lights, A/C, radio etc.. I assume (Hope!) I tripped a
breaker or blew a main fuse but am unable to locate it.

Answer
With a test light check the fusible links around the battery first,then the alternator, then the starter.
Fusible links look oblong in shape and are normally black,plastic and are incorporated into the wire. Remember to check both sides of the links.