It really doesn't matter because you will be customizing brackets and stuff anyway, but a Grand Prix and I think a Regal too will have the dogbone bracket that you can modify to work, will have the correct oil filter adapter, correct supercharger tensioner and correct steel oil pan (some other L67 cars will have aluminum which I believe is harder to fit, all L32 engines I believe will have aluminum pans though).. Pick the lowest mile and best looking engine, you can always swap the components on it.
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86 Fiero GT 4spd - L67 swap: VS cam, GenV
98 GTP - Some mods