First of all, they are not called bogies, they are just called road wheels. They basically go on the road wheel arm like changing a tire on your car. If you look at the center of the kit road wheel, you will see a ring of bolts. The center of the hub remains on the road wheel arm, the road wheels themselves are just the wheel.
A device called a "dog bone" (looks similar to a giant metal bone) is attached to the inside of the road wheel arm and the other side fits into the inside end connector of the track. When the tank rolls forward a few feet, the dog bone is rotated to a vertical position and lifts the road wheel arm up over the track a few inches. The dog bone is bascially a jack to give the road wheels clearance so you can remove them.
The lug nuts are removed and the road wheel is free to come off. The inner and outer road wheels are not connected. They just mount onto the same bolts. The "axle" portion that the two road wheels mount on is called the spindle. When both road wheels are removed, the shiny metal spindle is visable along with the series of threaded bolts that ring the hub. Road wheels are identical, one is just reversed when put on. Changing a road wheel takes about 15 minutes and is as simple as changing a tire (with a lot of lug nuts).