be careful if you do butcher yours, because if down the track it throws a code, you will need a functioning dpf to clear it. i believe they cost thousands to buy new. there used to be someone who sold recalibrated sensors to use with a delete pipe.
I wouldn't jump at knocking the guts out of the cat. If you suspect problems with the DPF, write to auggie (a user on this forum) and ask about his replacement sensors. They're not cheap, but they are absolutely brilliant and work precisely as auggie states.
When I bought mine, 2007 D40, its DPF was already removed (the inner filters and the mesh/honeycomb) where as all rest of the sensors were intact into the original mountings.. It worked with no codes till a mo month back when suddenly one day the DPF light appeared and it started giving black smoke upon sudden acceleration though was still not in the limp mode..
What I did was un-mount the two pressure sensors pipes/hosings from the DPF and connected them directly through a small piece of metal pipe, which did the trick and DPF light vanished along with the black smoke..
This simulated to the pressure sensors that pressure differenc is with in range and DPF is clean enough.. So not need to put a new DPF..!