It can be awkward handling the soldering iron and heat shrink gun when doing it that way. Strip insulation and fit each terminal on the bench. This is preferable for precision soldering. When refitting the harness you will have to feed the terminals through any bulkhead grommets a few at a time. The last few may be a tight fit.
Rubber grommets have to be fitted to every through panel hole of course.
See Making Terminations for my ideas about fitting terminals. Thats the end of this page. I've found this method of wiring effective. Your block diagram and wirelist should be carefully preserved as they will help you to navigate around your own harness when trouble-shooting or modifying in the future. Visitors should exercise their own judgement and seek expert advice about local vehicle laws before applying any of my practices to their own vehicles.