The 882's are your basic run-of-the-mill 76cc head. Nothing special but they can make decent power numbers. The 67cc heads you speak of will get you above 9-1 but not 10. Still a good power improver and if they're hi-po heads there's some power to be had there also.

Just a thought, the GM Vortec heads are proven power makers to 5500-6000 rpms. The ~$600 pr. price tag, excellent runner and combustion chamber shape and 58cc volume (which will get you around 10-1) would wake that motor up much better than a set of old 60's design heads.