1996 s10 swap to a 1995 s10 won't start

[carsharks]

My husband replaced a 1996 s10 2.2 engine with a 1995 s10 2.2 engine. We are having some aggravating troubles. He has checked all conections, and the battery. We have no interior lights, no gauges, no head or tail lights, it will not turn over using the switch. It's like it's dead. It will however turn over and over, but will not start, when you short out the starter. We have checked millions of times for pinched wires, broken, lose or what have you. Does anyone have any suggestions on what to try now. We're about ready to set fire to it. Note, then 1995 engine we replaced the 1996 ran great before we put it in. Also, the 1996 ran as well, but knocked, that's why we replaced it, so we know at the time, before we changed the motors both ran.
Please help.

[old_master]

The 96 has OBDII engine controls, the 95 could have any one of 3 different systems depending on when it was built. If the 95 is OBDII it will be easier to diagnose the problem. If not, you may have to swap some sensors, ECM/PCM/VCM, and some wire harnesses to upgrade the 95 and make it OBDII compatible.

This link will help with wiring:
http://www.autozone.com/shopping/rep...00c1528025048b

Check the wiring for the starter solenoid and battery feed to the underhood fuse panel first.