I'd already planned to try and use rear Honda Cub wheels on the front of the CycleKart, and they'll fit lovely. Just a quick change of bearings and they'll slide straight on to the 25mm spindles. I waited until the wheels arrived before I looked at lock-stops on the steering and its evident I need them as the wheel just touches the camber rods on full lock.
give or take so I'm happy with that. The added advantage of running the rear Cub wheels on the front of our CycleKart is we can use "massive" 2.50" x 17" Tyres...well compared to the 2.25" x 17" front Cub size.