Much as
@hgschnell has written.
Generate a new version of 1S0 containing no features at all, but ensuring that all the previous features, runways, taxiways, aprons etc. are disabled.
This will ensure that the original scenery isn't visible in the simulator ... unfortunately the airfield will still exist on the menus and maps/GPS etc.
Editing the the default AP915150 may or may not work completely satisfactorily.
In my experience, BGL2XML can have difficulty dealing with some navigation features, which will cause recompilation errors.
These errors may well be related to other airfields in the file and can require quite extensive "digging and poking" and reference to the SDK documentation, either to rectify the situation or to remove the failing feature, which can be related to VORs, ILS, and some other stuff.
In this instance, AP915150 appears to decompile and recompile, with 1S0 completely removed, with no errors

For personal use, this would be my choice, but for re-distribution purposes, I always have reservations about this approach as it may cause issues for end users further down the line.
When making modifications like this to default files I ALWAYS keep an adjacent backup, with an adjusted suffix, eg. AP915150.bgx, AND an adjacent text file, eg. AP915150.txt, containing notes of what changes have been made.
I seem to remember that some third-party software will recognise that a default file has been changed, and ignore it or refuse to load it.
This may cause other problems if wanting to make other edits in the immediate vicinity.
Good luck
