The oil port on the BB would be on the shell, that is the frame, not the bearings; you would have seen it by now if it were there, so I'll assume it's not. So the frame is very likely from the 1960's.
The fork serial number should be visible too, so I'll assume it's not there.
I'm not familiar with Carlton serial numbers, so I'm hoping someone else will comment on that.
No oil port on the BB shell. And no serial visible on the fork. The only thing I can see on the fork is in the attached picture. Is that an 8 or perhaps a cursive P??? I have no clue.
Also it could be a repaint/re-enamel job as there is a "glob" I discovered on the fork while looking for a serial #. But as I said before no experience with finishes on that level.
