so i did this today. it was the coolest work i've done on the galant yet, water pump replacement doesn't even come close.
i found one adjuster to be completely stuck (took like 6-7 baths in diesel fuel before it started moving), and one to be reaaaally tight (4 baths before free movement). the completely stuck one was the exhaust valve lash adjuster, farthest from the timing belt, and i think the tight one was somewhere on the intake side.
but now, after complete cleaning - no tapping no more!!! thank heaven, i thought i would die hearing this tapping sound.
also, i didn't have any helpers, so i just plugged the holes in the head with shop towels, as someone recommended, and when assembling it back - i just put plumber's tape (the white one that is very thin) around the lash adjusters and tied a simple overhand knot on top of each rocker arm. after screwing in the bolts about halfway, it was very easy to untie and remove the tape pieces.