and you may want to swap in an alternator for reliable power. here is a link to how it all works on these old vehicles
https://www.chevytalk.org/fusionbb/s...php?tid/75546/
or a you tube on a newer vehicle
https://www.youtube.com/watch?v=xBtT6OgMlao
or here for a diagram
https://www.danchuk.com/images/Downl...Sheets/410.pdf
or here for an explanation
https://www.hotrodders.com/forum/57-...wap-11003.html