I’m not talking about a splice just to be clear. Like you can just take a razor blade and shave some of the coating off the main wire and wrap your extra wire around that then zip tie it secure.Yes, I know how to do a military splice. In my application, one of 18 connections requires it. It does not appear that there is adequate room for me to do a good job, but I'll try first with the splice. If I can't pull it off, then its the t tap.
You can remove a small section of insulation off of most under the dash stuff with a Bic lighter and your fingernails. "Military Splice" is very reliable though, next best thing to solder.It takes some skill, but you can strip the coating off wires without actually cutting the wires.