It's most common on non-scratchplate guitars to have the singlecoils mounted directly into the body but some, like this one, have pickup mounting rings, just as the humbucker does. It's just that they're never as pretty as either direct mounting or as the humbucker one. When you take them out see how deep the hole is, if it's not too deep you may be able to direct mount them for a cleaner look.
By the way your intonation is very pretty but does it work? :D