I have a 1991 Jeep Cherokee Laredo with the 4.0l 6 cylinder motor the engine went out on me and I have replaced it with a 4.0 liter 6 cylinder motor from 1990 cherokee sport besides a few key places on the block of the motor they are relatively the same however when I go to turn the motor over I only have spark on points 1,3,4,and 6 of the distributor 2 and 5 don't spark I've tested with a good plug wire and used a screwdriver in the other end holding it 1/8 of an inch away from the block. With all plug wires plugged in and in correct order it will occasionally backfire . I've used the Hayes manual that they sell at autozone and I believe I have the number 1 cylinder at tdc then I set the distributor for number one plug. I am in a major bind seeing as this is my daily driver and the only transportation for my family and me so as y'all can see I'm in a time crunch . Please any suggestions on the matter are greatly appreciated. Thanks

Scott Phillips.