Was told the AX7 was from around 2010. Looks like it actually is from before 2002? Think the CRG is a much better choice. What is the difference in a KT and the -1B? Would this chassis work with 4 cycle fit wise? What size driver generally fit in a CRG without the porch extension? There are so many kart models out there. It is over whelming and not a lot of data online.