I am considering to just say screw it with the 50 year old wiring and just buy all new harnesses. I heard some people say painless wiring was the way to go is that true?
Yes and no. While the Painless wiring is new, it all isn’t color coded and wired the same as a MoPar is. There modeled after a GM. They are very good wiring systems, you just have to know the differences and understand wiring before you jump in. I’ve met a few people that really didn’t know electrical wiring as well as they thought and sold the harness when they couldn’t get it done themselves.
New, year specific wiring harnesses are available from/through Year One and other places. These are excellent reproductions of what your car was made with. I myself having used these found the connectors can be a bit tight and IMO, hard to fully connect to make contact. But they are plug and play as well as a high quality reproduction wiring.
The wiring comes in sections. In example, if you need the tail light wiring, you purchase just that section. I myself needed the wires under my dash in my ‘71 Duster, I purchased just that only. The fuse box was included. Make sure you order the under dash wiring with ether the OEM fuse box or with the blade fuse style you like. Standard or mini blades. If your car didn’t come with the electronic ignition, there are also harnesses that have that mode built into them as well.