Most problems with fusible links happen where the connection is made to the regular wire. Crimp connectors usually aren't good enough connections, resulting in heat buildup and fuse link burnout at the connection. I like to strip about 2" or so of insulation on both ends of the link, and a corresponding amount on the conductor I'm attaching to, do a TIGHT twisted connection, followed by a quick, careful solder job. Then use a piece of heat-shrink tubing to insulate the connections at both ends. You could also solder a terminal lug onto the fuse link where it attaches to the alternator, and just do one twisted connection to the wire going to the battery.
If the link fails after installing it that way, you need a larger-diameter link. Surge current from the alternator right after starting can go extremely high, and the fuse link is doing what it's supposed to do, interrupting what it sees as a short circuit. You could also install a high-capacity fuse holder, with a 60 or 80 amp fuse. Those are on some newer cars instead of fusible links.
Jerry
