 Systems Are Direct Fit? Majority of systems from XFORCE, Di Filippo, Manta, Msa, Ballistic are direct bolt. Below are some noted fitment issues with products: Headers - some components of the engine may need to removed. Please see some examples below Headers - VE/VF steering shaft needs to be removed to install headers Headers - HSV GTS GEN-F is a tight squeeze and 0 0/0" headers are recommended over 0 0/0" XFORCE Chrysler 000C catback - custom cat section needs to be fabricat