Hardwiring a Valentine 1 in an '88 M5

[Steve1807@xxxxxxx]

I have an '88 M5 and have a Valentine One that I've been using with the 
winshield mount and cig light adaptor. I'm interested in hard-wiring it in. 
I'd like this to be as non-destructive as possible. Any recommendations as to 
where to place the unit and run the wiring?

Thanks,Steve

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