Intermitent Starter issue Options

[914itis]

My starter was fine, until the weekend.

The weather was nice and I decided to take a drive; started fine. when I got to my destination, I turned the key and it attempted to start the car and the battery cuts off.
I have a 60 amp fuse on the red wires going to the battery, check the fuse it wast toast. I replaced the fuse and it blew it instantly as soon as I turn the key on.
Since there is a wire coming from the the main fuse that I installed from the battery to my amp and air horn, I isolated the wire and replace the fuse again the car starts fine.

When I got home, I installed a dedicated fuse for that amp wire.

Since then, the starter becomes a hit and miss. sometimes starts on the first try, sometimes i have to turn the key on and off before the starter spins. Sometimes it would start spinning for a short time and stops before the engine can start.

The starter positive wire is straight from the battery.
I know that there is an issue with the 74's where a relay is installed, but why would it burn the fuse to begin with?

All my grounds are intact.

Any ideas??

[timothy_nd28]

I'm somewhat unclear with the order of events that took place when this fuse blew. You were starting the car (key in the start position) then all the sudden the starter quit with the key still in the start position? At this point, you found a aftermarket inline 60 amp fuse connected to the battery that was blown? Then after replacing this 60amp fuse, the car will now crank over? If this is true, it sounds like you had over 60 amps running thru your ignition switch, which doesn't sound good. I would suspect a ruined or intermittent contacts within the switch.