Hi Pete,
Here's the file I mentioned in the FS2K2 General forum.
Page 27, Military, FA-18AsRAAF.zip - fsGauges shows 18 gauges are missing.
I was able to find almost all of the missing files as a part of Page 19, Military, fa18sngl_drp.zip.
The page 27 file says it is an upgrade package but does not indicate that any other files are required or where to get them.
Hope this helps.