I believe 87-95 use the same connectors and the transmission harness should be the same. I'll confirm that at the junkyard next week. The speedo is on the transfer case and doesn't come into play on a 4wd. The AW4 doesn't use any VSS info, only the engine computer. The transmission gets it's speed info from the rear output speed sensor that is on the tailshaft of the transmission. The only difference that I could find from the Renix to the the HO TCU is that the Renix sends 5v through pin D1 to the TPS. The Renix engine computer uses a TPS signal that is backwards, so on the Renix throttle body you will have a dual TPS. One for the engine computer and one for the transmission computer. The one for the transmission sends info just like the later HO TPS, so Jeep just tapped into a single TPS on the HO and deleted the 5v source from pin D1 on the TCU. So doing this with a carbed engine it is best to use the Renix TCU, otherwise you will have to have a 5v stepdown regulator to supply 5v to the TPS. But those are only about $10-$15.