I have a Nova pump that I wish to mount a scope for turkey hunting. I have bought a weaver rail mount and can drill and tap it myself,but I need at least a starting "in" hole or "end" measurement-ie; a hole pattern layout. Will some one oblige me and give me a measurement-I'll take either inch or metric. Lastly,would a thread locker be recommended or will it hold in plastic(?) receiver? Thks,pw.ps, I can list my email addy if someone had rather:) email the hole pattern.