first off you have an Si so you already have MPFI. you could use a stock si ecu but it would be better to use a p28. i think it would be better to undo whatever dizzy wiring you attempted, and return it to stock. you need an obd0 to obd1 conversion harness with subharness, and i would pick up one from rywire. since your using obd1 injectors with the obd1 engine i'm assuming, you need to remove the resistor box from the driver side shock tower area. its a grey box with a green plug. 4 red wires and 1 yellow wire i believe. all you need to do is take out the box and solder all 5 wires together. The map sensor on the new engine is located on the throttle body. on your crx its on the firewall. unplug the connector from the firewall and connect it to the map on the tb.