Concerning the spanner, we don't have to make one. I used the thinner prop I had, installed with six short (but long enough) bolts, tightened lightly. Then installed 2 M10X1 nuts locked together. Using a 17mm wrench on the inside nut and holding the prop (like a spanner), I've been able to unscrew the prop shaft which is normal RH threads. It was moderately tight but no trace of threadlocker. I will use a puller to remove the drive hub, the prop bolt holes don't go all the way through the hub. One of the six bolts is broken, I have to repair or replace the hub.

JF