Wasteboard clamp screw sizes

Just a little bit confused about the type of screw to use for the clamps if one were to follow the this:

The document states to use m6 threaded inserts. However on the documentation for making the clamps that attaches to this, it says that they used m8. For which size is the downloaded file designed for?

The M8 screws and tap are used for the reversed “jack” screws which are used to control the rear elevation of the clamp. M6 or 1/4-20 will work in the slot, depending on your threaded table / inserts.

I don’t quite understand. This screw screws into the threaded inserts right? Is this an M6 or M8?

The screws show there are M8 — they’re used upside down as depicted as “jack” screws to allow one to control how high the back of the clamps are — an M6 (or 1/4"-20) goes into the slot and into the T-track or threaded insert.

Sort of like this:

Oh ok, got it. two screws are needed, one M6 and M8. No mention of the M6 screw was made anywhere so it got me confused. What would you recommend for the length of the m6?

I found it necessary to lay in a stock of different M6 (for use on my Nomad’s threaded table) and 1/4"-20 (for use on my Shapeoko’s T-track) lengths — clamp thickness, plus stock thickness plus length necessary to get threaded and a wing nut on it more-or-less.