Which Opus version do you need it to work with? (Still 9 or is the profile info out of date? Newer versions have some easier ways to do things, but I don't want to give something that won't work with what you have.)
I don't have Opus 9 handy to test with but it will be something like a regular expression from
(.. .. ..) (.*)(\.[^.]+)
to
\2 \1\3
There are slightly better/cleaner ways to do it in newer versions, although that will work in them too (in fact I tested it with the Opus 12 beta). The main thing is it will not ensure it only matches numbers at the start, only three lots of two-character pairs.