ILS in PMI not working properly

Hi all

I have a question:

The ILS in PMI (RWY24L) is not set-up properly. When you follow the glideslope you come in way to high and end up landing half way down the runway. Larger planes are then unable to stop in time and overshoot the runway.
Is there any way this can be corrected by myself in the editor? A friend of mine and I have been trying to fix this and have tried everything under the sun, but it will always revert back to the default ILS.
The only thing that seems to work is to set-up a new ILS with a different frequency. When we do that all is great, but using a random frequency is less than ideal, especially since we would like to share our work.

Has anyone managed to successfully correct a default ILS?

Many thanks!