Kit bot wheels and chassis assembly

It has come to my attention that while assembling our kit bot chassis and andy mark wheels. We are just using the kit chassis and wheels or prototyping and my team is wondering if there is a quick ans simple solution to make an axle fit through the 3/8 inch holes on the chassis and the 1/2 inch holes on the wheels.

Buy 1.125 OD by 3/8" Bearings. Use a grade 8 3/8" Bolt.

what we did was drill out the holes to 5/8" and use an 1/2" ID and 5/8" OD flange bearing. The only thing that made we question this was that it removes the metal around the lowered hole completely in a small section. The bearing takes care of that load. It worked without problems for a regional and an off season event. It’s still running now.

All that i did with our six wheel drive was to drill out the holes to 1/2 in. and run a 1/2 bolt through with spacers between the frame rail and the wheel bearing. It worked great. I have used pillow block bearings and shafts also.