Big update:
Apparently the position data for VGSI are now being provided by the FAA! This seems to have started a few months ago. This is being updated every 28 days.
I strongly urge the Asobo folks to look into incorporating these data for correct placement, angle, type, etc.
Here are the data fields included:
ARPT_ID – Associated Airport Ident
RWY_ID – Associated Runway
VGSI_LIGHTS_TYPE – (VGSI_CNFG_CD) Type of VGSI Lighting
TH_CROSS_HT – (TCH_MSMT) Threshold crossing height
COM_ANGLE – (CMSN_ANGLE_MSMT) – Commissioned Angle
REF_PT_LAT_DEG – (LAT_DEG) – Reference Point Latitude Degrees
REF_PT_LAT_MIN – (LAT_MIN) – Reference Point Latitude Minutes
REF_PT_LAT_SEC – (LAT_SEC) – Reference Point Latitude Seconds
LAT_HEMIS – Reference Point Latitude Hemisphere
REF_PT_LONG_DEG – (LONG_DEG) – Reference Point Longitude Degrees
REF_PT_LONG_MIN – (LONG_MIN) – Reference Point Longitude Minutes
REF_PT_LONG_SEC – (LONG_SEC) – Reference Point Longitude Seconds
LONG_HEMIS – Reference Point Longitude Hemisphere
REF_PT_ELEV – (POINT_ELEV_MSMT) – Reference Point Elevation
REF_PT_THRES – (THLD_DIST_MSMT) – Reference Point Distance
The key to this would be using the reference point lat and long (which defines the threshold for the associated runway) and computing the REF_PT_THRES, which is the distance from the VGSI to the threshold. Unfortunately, there is no lateral position or spacing, but this would at least give the proper glidepath and TCH (assuming the runway elevation and slope data are correct).