The problem here is what your asking isn't about the Bonneville, it'* about the unit your installing. We can't say for sure what hooking up that wire will do. If I had to take a guess, it'* looking for a signal saying, yes, the parking brake is now on. If it were just a ground then you could connect it anywhere. Is there a wiring diagram with the unit? If you can scan that in and post it here we may have a better chance of helping you.
Also, keep in mind there'* a reason why it wants the parking brake on to work. I understand why you want to bypass this, but the law is the law.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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