AFAIK the only practical way would be find a 95 with TBI and swap the complete dash and all wiring under the hood. Shouldn't be too hard if you leave it all assembled. Might need to cut a hole in the firewall where the harness passes thru. Just make a pattern from the truck you get the harness from.
94 dash is different and 96 never had TBI so it would have to be another 95.
Only other alternative would be get copies of both wiring diagrams and build it one wire at a time.
To simplify thing you can put those not quite sealed ECM's under the hood. On my 94 with a TBI I relocated the ECM to under the hood on the passengers inner fender. I covered it with a larger piece of water and ice self stick roofing underlayment to protect it from any water thrown up when driving in the rain. I didn't seal it air tight to let it get some fresh air for cooling the processor chip. Drove it that way for 16 years. A case of terminal salt cancer finally took her from me.
If you wanted to get fancier you could fab a cover from some lightweight aluminum. Just be sure it extends past the connectors so water runs off the shield and can't drip onto the connectors. You could caulk the top of them to be extra secure. I didn't bother.