Had the same problem on my 1st FB in 75 after installing hedders.
Went thru 3 in 1 month.
If you want easy hot starting and theft deterent all in one, run a 8 or 10 gauge wire from the battery to a HD toggle switch, then down to the solenoid.
Install switch within easy reach, but out of sight.
While turning engine over with the key, flip the toggle to the starter.
Be sure to turn it off after engine fires.