I wasn't thinking, I've got 2 dado blades.... Thanks

Tom wrote:
You might try a 1/8th dado blade. Don't got no dado? I've roughed out the
underside of ZCI's to allow the needed clearance, so maybe use a router table
with a 1/4 inch plunge bit, stops,and a good workholding fixture. Take it to
your 1/8th limiting thickness where the blade will be aligned, then go to town.
I'm sure there'll be more ideas from the group.Tom
Someday, it'll all be over....