Okay so I replaced my suspect wire, and all i get is a slow rotation of the motor like the battery is dying, checked the battery and it has 12.85 volts. Anything else I can check short of pulling parts and replacing till I find the culprit and if so how would I go about checking them?
The current has to be able to make the complete circuit, from positive battery cable to negative battery cable. Sounds like all you replaced was the positive battery cable. That still leaves the solenoid, starter cable,starter and negative battery cable, assuming you
do have the negative battery cable bolted to the engine block.
If you have someone helping you, have them turn the key to START, and use your voltmeter to measure the voltage at every point along the way. connect the - lead the negative side of the battery. The BAT+ side of the starter solenoid should still read battery voltage, as should the STA side of the solenoid, and the starter cable connection at the starter. The engine block should read 0.0 volts . This check should tell you where the extra resistance is.