hey all on my brothers EF he had a blown tail light globe which caused the fuse to blow, i replaced the globes with the correct ones replaced the fuse went to turn lights on and the fuse blew, so he has no hazrads, interior lights or tail lights??? wat the hell is going on

could be the trailer plug
could be the boot light (can heat and short)
check all connections! I've seen the key light wires frey and short