Hugh---This oil gallery plug used to be sold 'four on the stick'. I
tried several methods of installing this aluminum plug, but none would
keep (high pressure) oil from seeping out of the block at this point.
Teflon tape, pipe sealer, Permatex, and half a dozen others, all
supposed to stop oil. Bah! I finally resolved this by using a 3/4X16x1"
hex head bolt. This particular bolt had a long area under the head
without threads, so when screwing it in it had a 'stopping point' that
would then put tension against the threads. (I think it was Berry who
gave me this idea)
If you use the stock plug, you can cut a slot across the end and use a
stubby screwdriver to install it. Good luck...