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There’s bolts across the top and the bottom, as mentioned in the guides around the place, remove the trim piece above the glovebox and the bolts will be visible on top. Bottom one can be accessed as is.
Have a look at these
Thanks stockies. With regards to the antenna I am using a glass mounted oneFrom memory its a 10amp fuse.
Would not trust it to power a UHF radio, but a relay could be used to switch it so its off when the vehicles ignition is too.
Would be best to wire it to the battery in the boot and hide the wires down the center console, under the carpet between the seats and run it under the rear seat (seat just clips in) and then straight into the boot via one of the access holes on the side. (remove boot carpet around battery if unsure)
Place some split tubing on any parts of the wires that run near metal so they don't get damaged, and jobs done like a professional.
Also, what would you be doing about the antenna?