When deciding on fuses you have to look at the wire gauge AFTER the fuse that you want to protect. NO good idea to have one big fuse and a few lighter gauge wires after the fuse so in case of an earth short these wires will go up in flames before the fuse blows. So big fuse only with big wires, lower amps fuses after a main fuse for lighter gauge wires to individual electrics.
Vic
Vic