I just purchased a 700r4 transmission mated to an np208 with a solid output yoke from an '88-'89 blazer. The tranny was new from GM like 1 year ago. Everything appears like it will bolt up just fine to my '79 350 and crossmember. I have a front driveshaft from an '84 that I believe is the correct length and I will have the rear lengthened or shortened as needed. The question I have is reguarding a four prong plug that is located on the topside of the transmission just above the left rear corner of the tranny pan. How should I hook this up? My '79 has no provision for electronics in the tranny. Do I need to rig up some kind of switch? Can I just place a dust cap on it and run the tranny without the electronics? What does it do? Is it just a neutral start/ backup switch? Is it a VSS or something I can ignore? Any help would be appreciated. Thanks. Michael. 82 Toy LB with Marlin, locked, 36's,38's,35's depending on month/mood. 79 K5 with 3/4 ton running gear, 36's.