old man

Hey people, I'm new to this world. I have a 03 ranger. Have only ridden it .5 miles since owned. Shut off while riding it. Found main fuse had blown. When I tried replacing it, it be low instantly. During trouble shooting. I found if I disconnect reg. Rectifier I don't blow the fuse. Then I was able to get it back in neutral. Checked the rectifier, it seems ok. But with it installed it blows the fuse. Can it test good and still blow fuses. Can't find any bad wires. Any thoughts