A fusible link needs to be short to do its job. If it is too long, it will add too much resistance in the circuit. Seems like 6 inches or less would be good. I believe the rule of thumb is two wire sizes below the main wiring (excluding odd sizes), so if you have 8 gauge wiring, you would need a 12 gauge fusible link.
Regular wire will work, but to be safe fusible link wire insulation will not combust. Fusible links get hot enough to melt copper when they function, so you don’t want to set the plastic insulation on fire, and maybe the car…..
