Yashica Mat lens removal question

I'm trying to remove the front taking lens in order to access stuck shutter blades.
I see where the spanner wrench indents are on the lens itself, but I'm not sure if the Bay 1 ring is part of the lens or if it has to be taken off first.
Does anyone know the procedure for this?

You have to remove the front plate first. It is hold in place with 4 screws covered by the leatherette.
After this you will be able to unscrew the lens.

Not for the faint of heart or the appreciation of precision tools, but you can look over this info-
Dead Link Removed

The Yashinon lenses have slots for a spanner wrench for removal. Then again, Tessars on a Rolleiflex look very similar, but the spanner slots are for removing the front element retaining ring, not the full front group.