This New alternator is known as the universal fit alternator
and will fit many applications. 
It has a 2 inch wide mounting foot and threaded adjusting ear.

You need only the main charging wire connected from the positive
post of the battery to the alternator output terminal.

This is a 100% Brand New Alternator complete with a Self Exciting Regulator.

Comes Complete with Coast Guard Approved Screens and Cover,
1-V Pulley.

Interchange numbers:
API Marine: 20051
ARCO Marine: 20102
Mercury Marine: 56045, 59755, 69729
OMC: 983424, 983836, 988247