There isn't much to it since the cord is a simple jumper from the radio to the glovebox.
The one trick is to know that the plastic clips holding things together is a center barrel (with 8 small barbs) that gets pried out from the 8-tabbed surround.


The left (or top) is the clasp together, the right (or bottom) is the barrel pried out so the tabs no longer hold the connector in the round glovebox hole.
If you create a 3/4" hole (measured 0.737"-0.818" on the grommet) the connector should slide right in and a quick push snaps it all together. It appears the connector can be mounted into flat material up to 0.114" thick, again by measurements.