I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission requirements unknown.
Leaving Lennoxtown on Glen Road you will come to a roundabout, turn left on to Newbridge and cross the river. You will see room for a couple of cars on the right. Follow the footpath which joins up with the old access road to the castle (a 1km walk through woodland). I TOAL from the forestry road west of the castle. Although not in the Glasgow FRZ, it is on a flight path, so keep an eye out, though I did tend to hear them before I saw them.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 27/10/2020. It remains the responsibility of any pilot to check for any changes before flying at the same location.