As far as the charger house connector goes I’d first try putting a 12 inch piece of stranded wire into the connector hole then using a piece of wooden dowel rod wedge it down along side of the wire making sure the connector pin makes contact. Maybe a couple of toothpicks will also work or a piece of solid copper wire. You could then attach the perimeter wire to the 12 inch piece. Do that for both pins.

If you can’t get a good connection then you can remove the tape from under the terminal house to get at the connector. Make sure you mark which is Red and which is Black so you don’t get the signal going the wrong direction. I’d solder the pigtails so you have a good connection.

Use stranded wire for the two pigtails as they will be easier to move around.

It doesn’t make any difference what you use for the perimeter wire, solid or stranded.

If you chose to go top side make sure you pin the wire every 18 inches or it will get clipped.

I pinned mine and there is only one spot where I can now see the wire. However, it’s a lot easer to find when I want to find it.

Note that one person suggested renting a cable pulling machine.

Have fun….toolbelt