tufcj
The V-8 flywheels are displacement specific. The I-6 flywheel is neutral balanced. All will swap, but I don't think the I-6 is drilled for an 11" pressure plate (only 10.5"). If it's a factory flywheel, it should have a casting number on the back side, that would help.
If your engine is apart, have the entire rotating assembly balanced with the flywheel you're going to use, then there's no doubt. The $100 or so it costs is worth the peace of mind.
Bob
tufcj