In vGPS corrected coordinates are shown as one of the columns. When you export the vGPS to a GPX file, or when you create a GPX from from a Geocaching pocket query, corrected coordinates are automatically used as the primary cache coordinates.
The problem is getting Project-GC to see the corrected coordinates in the first place. This is due to that there is no query PGC can use to pull all your caches that have corrected coordinates (or at least, not in the old API). However they can pull all your caches that have notes, so the work-around I use is that for every cache I have corrected coordinates I copy those coordinates into the cache note. See PGC > Profile > Solved Mysteries for more information on this.
