anyone w/ a d16 plz help~

i was workin on my car today and notice on the back of the head (beside the intake manifold on the distributor side) there is a spot w/ what looks like a small coolant resivoir and has two bolt holes on opposing sides for the spot there is nothing there.
to me it looks like there should be could any of you with a d16 the stock 90 si motor look and tell me if you have anything there?

eversince i got my car back from the engine being rebuilt i have been finding missing parts(they did a crappy job) any help would be apreciated

theres nothing there on mine either, i got no idea what its for, maybe one of our cali, euro, aussi or motherland friends have something though...some sorta crazy pollution control perhaps?? maybe its the altezza tail light fluid torque regulator flange?? gosh i hate altezzas and clears!!

maybe its the altezza tail light fluid torque regulator flange??

must be, i think its a vtec sylonoid not sure though