or you can keep the SL stub axles and use Traxxas 17mm hex's. I have done this and it works well. It might be a couple mm's wider than ROAR rules allow but won't make a difference in club racing with non-ROAR rules.
http://www.rctech.net/forum/electric...l#post13359235
Not 100% sure this will work on the .3- I still have the OG SCT410.