Thanks. The IMRCs do indeed look like crap, so I'm going to clean them.
I don't know how to test the PCV system, but I suppose that info's out there somewhere...
I did note the breaches of the gasket at 5 & 6. I wasn't planning to get the heads surfaced, but given that gasket issue and the difference in coloration on those cylinders, maybe high temps have warped the head. Does that seem likely? Also, is the block always assumed to be flat, so only the heads need to be assessed for flatness and surfaced?
As far as rolling the engine over goes, I still have the RH head on and the cams are all secured in position. I'm concerned about getting it out of time if I turn the crank.
Finally: With all of this, I am revisiting the idea of putting the 2003 tumble-port heads on, but I know they need a different manifold and adaptation to work on the '96. I haven't found any definitive list of instructions for doing this retrofit.