[leegreen]

>Use a non insulated crimp connector with double wall shrink tube whenever a connection is needed<

I respectfully disagree. I solder every single connector after crimping then put heat shrink on it. I also arrange all wires so they are supported / strain relieved within a few inches of the connections.

The only way a soldered joint in typical automotive wire will fail is if you create a stress point where the solder ends - the soldered wire is stiffer than the un soldered so if it flexes it is likely to break off right at the solder. But if your wire flexes that much it is going to break eventually anyway.

If you are using weatherproof fittings with built in strain relief like modern OEM stuff then maybe crimping is OK, but you need the proper tool / crimp die for every size you do to get good results.