Alright , this is what I did . The wire that goes to the starter solenoid you will now connect it to a conventional size relay pin 86 . pin 87 will go to a good ground. pin 30 you can (if it is easy to get to)bolt the hot/battery post of the starter solenoid . if you are going to do anything install a 20a cb there , pin 87 will now go to the start pin on the starter .
Draw this out on paper and look at it a minute . When you have your epiphany , get busy , look at where you want to route things and make sure you are happy w/your work . I did this years ago to a 5000 Ford tractor . It kept eating neutral start switches and I first wired around it . After standing next to it and starting it in gear , I fixed it w/this setup.