Definitely. I did a bunch of soldering on some of the accessory harnesses I made to link into the original wire harness. They worked, but honestly they didn't hold up all that well considering the fairly short amount of time I had most of them on the car. The crimped connections seem a lot more reliable. Definitely takes some practice to get the crimped connections right, but once I got the hang of it I think it makes a lot more sense.
Yes, they worked for all the crimps that are part of the harness. There's a couple crimps that are a little problematic, like on the ignition switch connection where you have a larger gauge wire. Technically I think the terminals included are probably right on the edge of being able to handle the gauge on a couple of the wires in the ignition switch pigtail, so you kind of run into a scenario where the double crimper is too big but the single crimper is a little too small. I definitely wasted a couple terminals doing the ignition switch connector.
But it's literally like 3 or 4 crimps out of the entire harness, and I think it would be an issue regardless. Pretty much everything else was a piece of cake. The practice thing helps too, you start to be able to compensate if you've got a little wire in a big terminal or a big wire in a little terminal. The terminals are just made to handle a range, but the crimp changes a little from one end of the range to the other if that makes sense. Gotta be a little more careful sizing and lining things up if the wire is the largest the terminal will handle.
