Proposed drive for Woody VI.The two 3-hole bits fit over the H shape and the 2 pins hold the assembly into the turntable.
The H piece is drilled out for a 1/4" rod which does not leave much left in the middle.
If this does not work I will cut a square bit of wood, drill holes horizontally for M4 bolts and vertically for the 1/4" drive shaft.
Update - no, it didn't work!!! far too much free play which meant that when the worm drive started turning it would have to take up all the slack before it would actually start turning the gearwheel. So it is either the bit of wood or I drench the whole thing in epoxy to stiffen it up. Better when I used 5-hole beams but still too loose.