what you'll need to do, since the electronics will change and the ignition system is different, is take all the wiring and non interchange parts from the 98 motor and throw them on the 95 motor... it will be rough, you will have to figure out how to get the DIS system working cause the 95 is distributor based. that means possibly putting your 98 heads on the 95 block... you gotta find out if you can use the heads, like what happened to the motor.? ya know... that will be the hard part.
you can always get the wiring harness and ecu from the 95 motor and just use all of that and splice some wires to the older ecu. the wiring is roughly the same, so it will be not TOO hard, but ti will still be a challenge.