To remove the damping rod allen bolt the forks have to be assembled but remove the oil first,you then have to compress the fork to put tension on the damping rod (I have a vice close to a wall for this) then remove allen bolt with an impact gun.
Those taper roller races are a pain to get out when cheap-skate manufacturers do not grind recesses in the headstock to allow for a punch to get a purchase. I use an old, large screwdriver, heated and bent to right angles that just fits into the recess behind the bearing ring.
Mike, Just been watching Chris Montignani's channel about a video on a 350 Griumph which has an interesting front end. Maybe a possibe solution to your front end issues. Love the channel, thanks for sharing.
Gosh, I thought I was the only one who had trouble putting different forks onto a bike. That was a troublesome episode, but you got there in the end! Your lathe is a bit bigger than my Taig and Myford ML7 though! Nice work Michael, thank you. Les in Chester 🇬🇧