HELP fusable link dies while driving

How big is the alternator? Sticking a GIGANTIC Great Big alternator on top of a 50 year old unimproved Mopar harness just might be a great way to blow things up

Read this MAD article:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

Is it possible the fuse link blew for "some reason" maybe even corrosion, and then was never replaced with one large enough?

Most these old girls go their entire lives without ever blowing one.