If you buy an aftermarket cd player, you can get a harness for your specific type of car (walmart or auto parts store). That way you don't have to clip the wires and solder each one.
A wiring harness is an organized bundle of wires that's usually wrapped with tape or tied together with zip ties.
For the best answers, search on this site https://shorturl.im/axbZn Buy a couple feet of 16 gauge THHN wire and some crimp-on butt splices. Use a wire crimper to strip the short wires, and butt splice a few inches of the new wire on to the short ends. Then connect the new wires to the harness. ACE hardware should have everything you need. An auto supply house might also.
A wiring harness is a plug in device most often used on your in dash head unit, it makes wiring easier because you can wire it while sitting down with plenty of lite then when you get in the car you can just plug it into the cars wiring and your ready to go...lots of modern autos also use a wiring harness for the speaker wires the advantages are less though because your only dealing with two wires.
