Thought I would take a moment to give something back to mud since Most every great idea has already been posted here. My 62 had a bad 2wd vacuum solenoid when I got it and I didn’t like the idea of the “always energized” 2wd solenoid. I replaced both with this:
It only hooks to the wires for the 4wd solenoid. In 2wd it is at rest. The 2wd line is under vacuum and the 4wd line is vented. In 4wd it energizes and the 2wd line is vented. 4wd is under vacuum. Mine has been working reliably since 2010. Just make sure to install a filter on the vent port like the oem ones have to keep the lines clean.
It only hooks to the wires for the 4wd solenoid. In 2wd it is at rest. The 2wd line is under vacuum and the 4wd line is vented. In 4wd it energizes and the 2wd line is vented. 4wd is under vacuum. Mine has been working reliably since 2010. Just make sure to install a filter on the vent port like the oem ones have to keep the lines clean.