I think the rear is slightly wider.. check that before you cut one up. it looks like you drilled the chassis for split blocks though so see if the holes line up and just mess with inserts.
I have a pretty comfy couch if it helps. will save you a minimum of $150 if you can get yourself out here.
I haven't been to other wcics races but just by shear entries alone, ours is definitely the one to try and get to.