Try using one of mine:
[INGRNLMP]
Name=Invisible Green Light Post
Armor=wood
Image=GALITE
Power=0
Sight=0
Crewed=no
Immune=yes
Points=30
Nominal=yes
Powered=true
Strength=6000
Explosion=TWLT070,S_BANG48,S_BRNL58,S_CLSN58,S_TUMU60
TechLevel=-1
Selectable=no
LightRedTint=0.01
Insignificant=yes
LightBlueTint=0.01
LightGreenTint=0.30
LightIntensity=0.001
InvisibleInGame=yes
LightVisibility=1750
DamageParticleSystems=SparkSys,LGSparkSys
It gave me this result:

That's the best result I could get, and it looks like it's glowing
Perfection can never be achieved; it's merely approachable.