> Off comes the head, and the first cylinder is about halway up.

Doesn't sound right. At TDC the #1 piston crown is pretty much flush with the block deck.

> My owners manual says it's 9 DBTDC. Is that 9 degrees back
> from top dead center?

9-degrees BTDC is 9-degrees before top dead center. Usually in crank degrees.

That's probably an ignition timing number which has nothing to do with cam timing for the purposes of removing and refitting the head.

> I marked the crank pulley so I can put it back how it came off.

Why did you take it off?

What for did you mark it? There's a key between the crank snout and the pulley. There's also a pointer on the timing chain cover and corresponding graduations on the pulley.

> So can you zero everything out when putting the engine back
> together?

Did you turn the crank while the head was off?

Is the cam sprocket tied to the chain so you don't lose the chain-sprocket relationship?

> What parts get sealant?

Depends on what you took off but basically only the vertical surfaces of the top timing chain cover/distributor housing that meet the head, and a dab where the ends of the horseshoe gasket meet the head.

> It looks like there was some on the head gasket.

The factory doesn't use sealant per se but there might be a coating on the head gasket that acts as a sealant. Usually the head gasket comes off pretty cleanly. Minimal scraping preps the block deck for a new gasket.

> The intake and exhaust gaskets were rather dry, so I couldn't
> tell if or when they had sealant.

No sealant for either manifold gasket.

> The instructions didn't say anything about application of gasket
> sealant in the assembly section. Does anything get sealant?

As mentioned above.

Sixto
95 S420
87 300SDL