This is the little O-ringed dowel in the front of the block head surface that aligns the head along with the rear bolt sleeves, and it also supplies oil to the head through a small orifice. Anyone got a part number or how to take one out? I milled my head and then drilled out the plug port in the head a little deeper and now it wont seal, looks like the rubber O-ring is rock hard and no longer sealing. I dont even know how to get the thing out. Its actually out of a 82 B2000 but figured there may be more 626 users out there, same motor plus we had one of these back in 85 as well as my friend had an 80 sedan, cool cars!