ORIGINAL: litterbug
It doesn't necessarily have to be a .90 size and up plane. For instance I put this engine into a 60 size edge 540. A lot of people are putting this into a 60 size plane, but you may find that there is not alot of room to work with.
Biggest problem with that theory is that such models are very lacking in the total wing area.
Such models generally aren't as stable so equipped as they were originally designed to be with the correct engine.
It's doable, just not a very good idea.