I currently have a MARRS SRX7. What would, in general, be the kinds of things to start modifying in order to move up to IT7 ( with hopefully then to G-Prod. ) I have a general idea of what it would take, but I'd like to get a feel for what the best modifications are to make. I believe that, at this point, MARRS SRX7 and IT7 are GCR compatible. 2007 will make the autopower cages illegal without more passenger door bars, yes?