[69a]

If you are using the suspect battery as the donor it will only eliminate the solenoid as the culprit.
Avoid any sparks under the hood, especially if you have been charging the battery.
Get your jumper leads and connect one end (one red one black) to either side of the solenoid, then step back and jam the other ends together. That will eliminate the solenoid.
Or connect one end to ground and the other to the starter side of the solenoid. Connect the one end to the positive side of a known good battery (your daily driver) and jam other end to the negative. This will tell you if it is the starter or the battery.