Electrical Wiring Tips
Do not strip a single wire until all of the boxes are mounted in their final resting position.
Make sure you have good clearance from the connector to anything else, you don't want any sharp bends.
Once the boxes are wired draw out the most effective daisy chain for the can bus. Also note where other wires will go.
Figure out what wire supports you will need. Grommets or plastic adel clamps or whatever. Install the cable management now.
Once everything is mounted and wire management is sorted and you are sure of what goes where, then, and only then start working with wire.
When working with wire, try to trim all of the wires going to a common box at the same time. Tie them together with lace, then trim, strip, and install the pins.