Use your Shop Manual to remove the Fork Cap assembly from your forks.  The assembly looks like this:

Grind the shaft above the nut to remove the roll forming.  Remove the nut and then the piston and valves.  (Do one at a a time incase you get confused.)

The short steel shaft will unscrew from the long shaft. You can loosen it with a pipe wrench. Piston and spring can then be removed.  It will look like this

Remove air release screw, drill through cap with a "R" size (0.339") bit. Hold cap securely in a vice.

Use 1/8"x27 National Pipe Thread tap and tap down to height shown.  (This height does not matter, it just looks better if tapped deeper)

for "Standard Bars"

Wrap the fitting with Teflon tape and tighten it into the cap using a 7/16" (11mm) wrench.

(for "Fat Bars & 4 post triple clamps)

(for "Fat Bars & 4 post triple clamps)

NOTE HOW IT MOVES THE TANK FARTHER FORWARD