Get a small box, spst toggle, momentary pusbutton switch, 3 alligator clips, and 3-10' lengths of wire, red, purple, and yellow.
Attach the alligator clips to the wires.
Mount the spst and momentary switches in the box.
Wire red to 1 post of spst and purple to second post.
Wire the momentary to the second post also. Connect the yellow to the other post of the momentary.
Now any carbed boat you're on:
1) Connect yellow to the remote starter relay.
2) Purple to the + coil
3) Red to any hot battery connection
4) Flip the toggle (ignition on)
5) Push the momentary (starter cranks)