Good idea to wire in a fuse on a one-wire?

My alternator wire joins the 2 gauge positive cable going to and at the starter. I choose no fuse.

What master disconnect switch do you run?

Same as above and run Cole Hersee 75912 or two constant duty solenoids.

I use a 150 amp fuse on the alternator wire to the master shutoff (just in case) something happens. I am more concerned about it when towing, I guess.

You can also use one of these. Pretty simple. Used in the trucking industry especially with lift gates