Part #'s for the fuses, fusible links, and breakers used in 1980 - 86 Ford trucks.
The EVTM says "The fuse link is a short length of wire smaller in gage than the wire in the protected circuit. The wire is covered with a thick non-flammable insulation. An overload causes the link to heat and the insulation to blister. If the overload remains, the link will melt, causing an open circuit."