Guitar power chords - how do you "open" them up?

Hi, so I’ve been trying to learn to play Red sky by Status Quo – only problem is, it’s meant to be played on an electric guitar and I’ve got accoustic. The chords were obviously invented by an insane african witchdoctor or some other mad scientist and are both impossibly hard (stretching across 5 frets) and sound like crap if I try the simplified versions. So… my question is this – is there a way to turn power chords into open chords and whether it’s a case of a simple E5 to E, G5 to G etc. translation or is there more to it than that?