Thanks again. Yep, saw diameter was 3”. I’ll check my holes tomorrow. I also see cables can be inserted without being stripped. Is that what you meant by “hats”?
I guess my biggest concern, and what I was alluding to in previous post, was whether I could locate and then disconnect any transformers from below? It’s going to be a devil of a job removing insulation, “plant pots” etc, then wiring while lying precariously in semi darkness.
Thanks again.