WTB Selec-Trac Vacuum 2wd/4wd Toggle Switch
 

For 84/85 Cherokee/Wagoneer with Selec-Trac ... may also be same on later years. Email me Russ at VH2Q dot com thanks much

Really rare piece. good luck with ur search. I have never even seen it in person

OK well since this part is unobtanium, we took it apart and found a square O ring that had disintegrated. Part of the O ring appears to have been sucked into the vacuum line as we had to run a new line to the switch as well, in order to get vacuum to the switch. Anyway, we replaced the O ring with a round one of the right(ish) size and it now works.