Advice on dry-stone wall fixings

[Verdigris]

I’m fixing some solar lights to a dry-stone garden wall. I’ve attached Fischer M8 threaded studs to the lights and poked these loosely into existing gaps to find the best locations. Now I just want to set these studs a bit more securely.
I guess I could use plastic plugs set in some sort of resin mortar, but is this going overboard for attaching lightweight fittings?

 

[Cubist]

The normal approach is to fix this kind of lighting to a wooden stake or post driven into the ground. Disturbing a dry stone wall is never a good idea.

 

[Verdigris]

Thanks Cubist, I'll use wooden stakes as you advise.