This style is the most talked abaout afaik - https://www.etsy.com/listing/1172990836/vertical-mounting-table-fixture-for-cnc
Anything on the front of the QCW would have to be custom made - but that insert itself could easily mount to the front (Extend 2 boards over the QCW by 3/4" to screw directly into the vertical frame and you build something off the bottom to hold it steady and you are in buisness
The spindle will cut quite a bit over the front edge of the QCW
EDIT: most of these are not QCW - but may give you some ideas… Show us your vertical clamping methods!