What are they? Cylinder head hex "plugs"

[Divot]

There is a hex "plug" located on the cylinder head between and behind the front and middle spark plug wires on the right side of the engine and one located between and behind the middle and rear spark plug wires on the left side of the engine. 

I have been noticing a small (very small) amount of oil collecting in the valley between the front and middle carb tubes on the right side.  The hex plug appears tight, but I have no idea where else it might be coming from.

Anyone know what these plugs are for and where a bit of oil might come from?

[Hook#3287]

I don't recall any real discussion on these "plugs" but didn't do a search here either.  My thoughts are they might have been part of the casting process and were not actually plugs, but looking at them (there's 2, one between 1 and 3 intake and 1 between 4 and 6) they seem to be removeable, but, I could not find them as a part here.
https://www.partzilla.com/catalog/honda/motorcycle/1999/gl1500ct-a-valkyrie-tourer/cylinder-head

or mentioned in the OEM service manual.

If they are plugs, I believe they might be associated with a Goldwing 1500, but no proof of that.

If your sure it's oil, maybe the Dragon Drool Tube is compromised.  Maybe part of the smog system?

I'd check the backside of the intake bottoms.  Maybe one of the o-rings is letting fuel leak and after drying leaving a stain that looks like oil?

I will say after 27 years of owning a Valkyrie, I've never messed with those plugs. Never had a reason too.