Yes, hook up is the same. I can't remember either but I think it is the negative side. I'd do the same as mentioned. Try it, if it doesn't work, change it. Also, you may need to configure your tach for 4 cyl if I remember correctly. Yes, I know, that sounds weird. Trust me, I read it on this board today. If you have the Mopar TFI, your tach needs to be set for 4 cyl. Do a search on Tach. You can read for yourself. HTH
85 CJ7 4.0L/SM465/Dana300/AMC20/Dana30, MPFI,154K miles - 33" 12.5's Pro Comp MT's, one piece axles, Detroit Softlocker rear, Lock Rite front, Warn Hubs, 4.56 R&P, 4" BDS lift, Warn x8000i, Warn winch guard, Hi-Lift, Tuffy console, Four X Dr. rocker guards, Rock Hard sport cage, Kilby OBA with 1.75 gal tank and York 10.3cc compressor, Tube fenders by GenRight Offroad, Fabricated rear bumper and tire carrier.