and the engine is completely different to a stock Ecotec too
Ah no it's not, it's not that different.
The L67 Supercharged uses the same block, the heads differ only that they're machined to except injectors, to clear the S/C.
Rocker covers differ in shape to fit around the injectors, fuel rails, the inlet manifold is completely different to except the M90 supercharger.
Ignition coils and sparkplugs are slightly different as stock, as are fore mentioned loom. S/C has 36lbs injectors, tune, stall convertor (2500rpm?) etc
I think the cam in the same as Ecotec L36.
Pistons and conrods are different (9.4:1 CR Ecotec vs 8.0:1 S/C and larger gudgeon pins. The USA L32 S/C has 'powered metal' conrods) as is the balance weights.
External differences in top radiator hose, belt drive and idler pulleys etc