On my 89 Formula 350, there's a fusible link with a plug that comes off the positive battery terminal..it is very close to where the positive battery cable connects to the battery. This plug is where the positive battery cable and wiring harness for the cooling fans come together...so its one wire on each side of the plug.

Anyways this wire is the positive feed for the cooling fans and it keeps getting too hot and eventually melts. I replaced the plug with the same factory plug that has the roundish style metal connector and a male pin style connector on the other end.

I'm wondering if there is a better plug out there that can handle the cooling fans better than this . . . or is something else wrong?

 

That connector set should be able to handle the 250W of the cooling fans without excessive heating. If you have a high current ammeter, you might want to measure the current draw of each fan.