The Drivers Ive got in the box of parts are from old used bikes. The cogs were hooked so I took an angle grinder and cut through them, then used a chisel to break them. Not grinding upto the threads.

The Freewheel blocks I have are from old deraileur gear bikes. From 5 speed to 7. A few different makes.
As I said I was thinking of using the 5 speed Maillard freewheel block. This will need a spacer on the axle. Probably a longer axle too. If I fit the block to the driver. Then fit that in the hub. Then fit the bearing cone and spacer in there. How does the cone sit still when I tighten the locknut.

I guess I could assemble the hub with out the freewheel on it. But would have to geuss the width of the spacer.