They move those plugs around on different models , but I think the plug looks the same.
Same kinda plug as in the O2 wiring harness. It has a snapon piece/cap that looks like 2 wires should be comming out. Take the cap off and there is only one prong.
I bet it's along the firewall, probaby where the main harness comes thru the firewall.
I'll check Thurs. at the library alldatapro program if nobody else helps you first to find it.

dave h.
'89 Raider V6 5spd;Aisin Hubs;; Gen2 LS: frt. brakes, rear coils;U.C.arms;R.trailing arms;idler arm; rear LSD axle w.disc brakes ;2 battery system for Dog's fan; relocated ECU; custom bumpers;J.Baker receiver;Conferr roofrack; t-bar crank.