Geda, the Marzocchi forks tended to be longer from axle to crown than equivalent travel forks from other manufacturers but I can’t remember which year they corrected this (or indeed if they ever did).
In general, I tend to recommend 130mm travel forks for the PA as that’s what I designed the geometry around.
However, I think pretty much every fork has been used on a Prince Albert at some point since they first came out in 2004 (I remember chuckling when I saw one with a Junior T on it), so if the 150mm Z1 floats your boat just try it. I doubt it will snap your headtube off. Nobody’s done that to a PA yet. Just don’t come crying to me if you ride head on into a tree and the top/down tubes crease 😉