The
2001 LMP07's diffuser is very similar to the LMP1's. The only outward
difference is the distance between the engine and the inboard most strake
(which makes sense as the new Panoz V8 is much smaller than the old pushrod
motor) and the sharp corner where there once was a radius. See the
LMP1 diffuser to compare. 
Looking
underneath, highlighted is the start of the flat bottom and the centersection
of the diffuser taken up by the engine.