Hi there this is my problem: I removed the old tape deck out of my 1996 Bayliner w/ 120HP Mercury Force Outboard and am having a problem finding a place to hookup the acc of the deck so it turns on and off with the boat key. The only place to hook this up is off the switch to a wire that goes back to the engine which I assume fires the engine up. Would there be any problem coming off of this wire or is there a better approach to this?