Does anyone know if the instrument panel main wiring harness is the same between an 84 Grand Prix with a 305 and an 86 Grand Prix with a 231? I need to know because I'm going to swap the 84 305 into the 86. I'm sure the engine compartment wiring harness is different since the map/baro sensor on the 84 is a 3 wire sensor and is a 4 wire sensor on the 86. Any other things you guys have run across with this kind of swap please feel free to offer that advice also. Thanks.