First question, "Do you have a service manual?" If nothing else the 74 electrical is much different than 73.
You can download the 73 manual free from MyMopar. I posted the 74 wiring section which you can download
Go here
Free service manuals
Go down to post 64, and click the black icon and "save as".
Also go to MyMopar and download the free 2 page 3rd party diagrams. These are NOT complete and do NOT show all options or connectors but they can be easier to follow:
Wiring – MyMopar
Click on 1974 and unzip them. I have no idea why they chose to post them in that fashion, they used to be individual files
