The core support sitting higher on 240s than 280s should at most require 2 longer screws from your local hardware store to reach. all the forces on the splitter are pushing down so it doesn't have to sit flush with the core support just hanging from the core support should be fine. It looks like the turnbuckles are the main source of stability anyways. oh and I can confirm if you are running a xenon/urethane air damn you will need longer bolts for the core support as the flexible airdam does indeed seem to hang lower I have one on my car and I can confirm that the splitter fits although the front turnbuckle mounts contact the recessed portion of the xenon airdam inboard of the brake duct holes you can either slot the holes for the turn buckle mounts and move them aft or just live with the splitter hanging 1mm lower than it should at the very front.
Edited by Cheesymamba, 07 May 2016 - 07:59 PM.