A spoke front wheel will bolt directly to the F2/3 forks. Keep the axle assembly the same as with K forks: the head of the axle on the right side, then the K speedo drive (or equivalent spacer). On the left side, use the K spacer, and the axle nut. This will center the wheel in the forks.
The spoke wheel has the brake rotor inboard of the F rotor, so spacers approximately .130" thick need to be fitted between the bracket and the lugs on the fork leg to center the bracket over the rotor. To add a rotor on the right side, the spacers need to be thicker, like about .245", since the K hub isn't symmetrical. All other issues with dual disks on a K fork, like the speedo drive, are handled the same way.