I don't know the center to center measurements on Hiboy Gal's roadster chassis. The coilover angle on the DF chassis is about 70 degrees. C9's should be close to this. The upper spacing should be around 31" to get the DF sway bar to fit. To get the 60 degree angle Aldan calls for, the spacing at the crossmember would have to be 26-27". Would this be too narrow to give the coilover enough leverage?