Thanks for the help guys, now I know that freeze plugs go in there I took the air pump mount off and measured the hole. It's .685" so I need an 11/16" freeze plug.

So I did a search with Google and came up with a place in Wales in the UK that does Imperial freeze plugs and ordered a set of 11/16" dia cup core plugs they comes in packs of three!

We call them core plugs over here.

Now that takes care of the air pump side. The power steering side looks a bit more complicated as the altenator mounts through the aliuminium bracket on that side. Any sugeestions for that side would be appriciated.