Go-kart tie rods are used to link the two outside forks to the center steering tube.
Before welding on the steering connector plates to the bottom of the forks make sure the forks are in perfect alignment. I use a steel rod for this.
Then make sure you employ a bit of Ackerman steering geometry to the steering plates on the bottom of the forks. Again the Atomic Zombie plans have step-by-instructions on achieving the correct steering geometry. Pictured below you can see the steering tabs welded to the bottom side of my left and right forks, respectively. [Remember you’re looking at this forks from the bottom.]
The center steering plate welded on to the bottom of the center steering tube.
Connecting the steering tabs with the tie rods.