Road Runner Nest

I am trying to find specifics and so far have have found the accessory wiring diagram in the Chassis FSM Regarding this option. Does anyone have this on their cars? I think I have the proper buzzer, #3579202 but I need the relay. Would 3488391 or 3879519 be correct? Relay location under dash frame between glove box and ash tray? Buzzer location? I could be all wet with all of this. Trying to put the pieces together, I think this would be a neat option. The accessory wiring harness for these (3) terminals is probably near impossible to find. I figure it will just have to be custom.

Thanks in advance guys, I love this group!