Much depends on where the installation will be used and the voltage of it, and the current it's got to carry. Automobile connections - which are normally for 12 volts - can be spade connectors or...
Use this to hook up to your new harness that has alot less confusing pattern
They almost every year,make, model
Car Radio Battery Constant 12v+ Wire: Blue/Yellow Car Radio Accessory Switched 12v+...