in the beginning i was just eyeballing the parts, then I found that someone has swapped the makita driver anvil with the impact wrench anvil here in GJ, so i said why not try it because makita service center is just 10 mins away from my place, so I passed by today at the makita service center and talked to the rep to check the parts if it would be the same diameter with the driver and the wrench, we measured it with a caliper and it was the same, so I bought it and i putting it in my makita, i said why not try it on the ryobi first and i was surpise that it went in and no wobble at all, everything just fits in, it was very easy to swap and very straight forward. Now everybody can enjoy the cheaper 3/8 impact wrench conversion, since Ryobi Impact driver is very cheap specially the blue ones.