I think 16 ga on the relay trigger terminal is fine....it carrys very little amperage as all it does is click the relay primary circuit. I would pack up a couple of 30s, 40s and 50 amp main fuses for the glovebox, and then stick in a 25 amp main. Turn on all lights and crank up the bass ind volume on stereo and ride, trying in sort to blow that 25 amp....if it eventually blows, use a 30 and try again to blow it.....if the 25 never blows with all fuse block accessories, leave it in.