The POCO will dictate where the metering enclosure is to be mounted. If you have never seen it like that before (me neither) then you need to check with the POCO as to where they accept the CT meter. Out here (New England) we have to purchase and install a separate CT/PT enclosure, usually as part of the main disconnect, then the meter can is remotely mounted outside the building.
4-1/2 inch conduit? I've never run across it before. Maybe it is metric, then rounded off?
