I pulled the top out of the vacuum press, and had a nice wonderfully tight fit.
In the meantime, my toys had arrived. Paddle power switch, Woodpecker PRL, and a PC7518.
I created a small jig to match the exact outside of the top of the lift, minus a half inch around.
Then I rough cut the hole with my crappy ancient craftsman jigsaw, and made a note to get a nice new Bosch, and then I used double sided tape to stick the jig to the top of the table, and then used my router and a flush trim bit to mate the size of the hole in the top, with the size of the jig I just made.
Then, before taking it further, I lined up and prepared the Dado for the Mitre Runner. I think I may replace this with a T-Track mitre runner though.