any tips and tricks for splicing into old brittle wiring?, need to replace the wiring to the tail light switch Options

[bradtho]

first thing first, I've tested the reverse light system and the switch works fine. If I squeeze the snapped wires together I can get the backup lights to turn on.

So I need to replace a section of this harness. I've used a solder iron before and had success, but its not like I really know what I'm doing.

1) I'm going to need to remove the pin connectors and put them on my replacement wires. I'm assuming I can separate them from the old wires reasonably easy with a normal solder iron and simple re-solder to new wires. anything else I should expect here? My understanding is these pins are NLA, so want to make sure I don't ruin my good existing set.

2) the wire is pretty stiff all the way back to the engine tin. I'm hoping to replace as little as possible, maybe start with just 2in and see if I can get it working. Is that a bad plan since it's likely to break again? the wires inside the engine comp aren't nearly as stiff. I'd like to keep the existing harness. solder? butt splice?

Is this a losing battle with 40 yr old wires?