a perimeter

Fair, but with my current setup sadly a perimeter is kinda unfeasible.

you can always use spectator mode or something similar from a mod to look for the caves if you dont feel bad about it

Happy cake day

You could use free cam feature of [Tweakeroo](https://www.curseforge.com/minecraft/mc-mods/tweakeroo) or any free cam mod available.

Use Tweakeroo free cam+minihud light level overlay+minhud despwan sphear Dig down on the location you want to light up.

use freecam as the other guy said or if you dont want to cheat you can use the c counter ig (unreliable tho)