A '92 might be hard to pare down since it uses a MAF so you would have to keep the mass airflow sensor no matter what to keep a good spark curve... That said I'm sure you're probably using a CA100 maybe a CA200 woodward or Impco mixer so if you put the MAF in front of either you would be fine...
There's a wiring harness diagram in the tech library I think in the turbo area for a '91 which is the same as your '92 engine, take a good look at that and get rid of the fuel injectors, oxygen sensor and EGR position sensor (maybe check the resistance of it and add a resistor across the wires if you want to keep a check engine light) and pretty much everything but the MAF, coolant temp, air temp, crank sensor, DIS module and any related wires and that should be about enough... If you want to keep it in open loop to keep the check engine light off for your application a resistor across the computers coolant temp sensor at around 70F should do (put the sensor in room temp and check resistance across it)
Shouldn't be too hard, it's a simple engine system...