It would be better to show which disk is on the saw. It is clear how to partition

Anyone know what disc to use as there are so many out there?

Or use an appropriately sized saw. An 18-1/2” worm-drive provides a more than adequate cut depth. I would also recommend a respirator and sealed safety goggles as opposed to safety glasses and no mention of a mask at all.

What about ear protection, do you not need that using a circular saw 🤔