The kiteboogie: keep your tush 7 inches off the ground and go way too fast

Step 9 The steering column

Now you need to drill a clearance hole for the steering column to come up through the cart body. The clearance hole should be 1" to clear the 3/4" pipe. Drill the hole at the mark you made for the steering column on the plywood cart body. Put a piece of 3/4" pipe through the hole and make sure it moves smoothly. File out the hole a bit until the pipe can rotate pretty frictionlessly.
(I know my hole is ugly, but it just had to be a clearance hole and I didn't have a jigsaw. I've since bought a jigsaw--I actually just got back from the hardware store)

Now center the 1" flange fitting over the hole you just drilled and mark the four bolt holes. Drill them out and mount the 1" flange onto the cart body.

Screw the 2 inch long 1" nipple onto the flange