Your chances are slim to none. Bore spacing must be exactly the same, bolt holes need to line up, water jackets, oil passages, oil drain, and the critical timing gears/chain must line up exactly or it will wear severely. Knowing the Saturn is far more undersquare than the Opel (small bore/long stroke), the bore spacing is likely off by a lot.
Why not put the complete Saturn SC2 engine in? I'm not much for engine swaps, but at least the Saturn is a GM engine, all aluminum, and does have reasonable hp (123). And it's even a 1.9 litre, for what that's worth. I had actually contemplated doing this swap to my father's GT years ago, until I came to my senses...