Fusible link?

Maybe I'm making this harder than it should be, but I bought a 14 circuit kit from EZ2 Wire. I see on the diagrams you should have a fusible link installed on the main power wire going to the starter relay.

They provided a maxi fuse "50" but I can't figure out how to wire it in. Shouldn't the fuse have a holder or plug or some type of housing?

Thanks,
Wes