Zero Clearance Table Saw Insert and Space for Riving Knife

[Wind Gatherer]

Hi all,
I'm making a zero clearance table saw insert, see attached. I'll bring the blade up from under to cut the slot. Though to do this I'll need to remove the riving knife. What I'd like to know is, how do I make a continuation of the slot for the riving knife to rise?
Cheers,
Peter.

[yourdoubleglazing]

you could natural let the say cut its line, take the table back off and manually cut the space for the riving knife. Ive done this before but not have explained it very well.