Hey folks--yes, I searched the topic, and didn't come up with anything too helpful... The motor was a running CB400f with only 5800 miles. pistons move freely in the cylinders and the heads came off fine. I've sprayed pb blaster down the cylinder studs and around the base gasket. I've tapped every so gently around the fins with a mallet. Doesn't seem to want to budge...
Any other tricks out there? Thanks!