There is a large issue when using an '87 to '91 harness on a '92 to '94 J-body, and that is how a lot of the wiring is routed between the engine bay and interior.
Just to mention the wiper motor control wires on the '92 to '94 route through the passenger side bulkhead feed through, where as the earlier version were routed through the driver side feed through connector.
'92 to '94 has ABS, which has the rear axle wires routed through the driver side feed throughma nd incedentaly enough if you don't modify the wiring you will have the right rear ABD sensor connected to the wiper motor, using the older engine harness in the newer car. :lol:
You'll be much farther ahead to get a V6 harness from a '92 to '94 Sunbird, as this will pretty much drop in.