Had not started boat in a couple months.  Hooked the muffs to it and fired it up. Cranked quite a bit before it started and let it run a few minutes..  Then I  pulled the cowl off and saw wiffs of smoke! Found the yellow wires from the voltage regulator were melting. Followed the wires and the only place they were melting was near the voltage regulator.

 

Priced voltage regulators online range from $39 to $150 for OEM. Are the cheap ones a waste of money?

Sorry, but I don't know enough about those black motors to help.  To over heat a regulator like, I would be very suspicious of the cranking battery and also might want to look at the stator's charging coils.  Also, make sure it is the regulator,  Mercury was good about not even putting regulators on their smaller motors.  Especially the older ones.