I was thinking that, if your cats were in fact damaged due to the rapid cooling situation related to touching snow while at operating temperature (not extremely likely but certainly possible), some kind of a heat shield on the bottom might protect them.
I agree. Also, I'm pretty sure that is the cause of the said "noise" because it started happening after my drifting adventures in deep snow...

---------- Post added at 04:35 PM ---------- Previous post was at 09:52 AM ----------
More pictures of the new painted '06 grille and painted/tinted tails
The blackberry storm pictures weren't cutting it...
Grille, from a 2006 FX, on my 2005 FX. The clips on the back needed to be trimmed for it to fit correctly because technically the 06-08 grille does not fit the 03-05 bumper (just the clips differ) plus, I like the newer grille style better.
Paint-tinted tails. Look like straight up black paint from some angles, others you can see right through it to the chrome details. There is a slight goldish tint to them because of the dark chrome inside the tail lights.
and so you can see how the tails are still semi-transparent

plus, light still comes through perfectly
fixed headlights and fogs! sans kptech module

another "mod"
I finally trimmed down the plastic on the cargo cover so that is sat flush on top of the subwoofer box...I thought it would reduce the vibration it was causing. I sanded it down on a belt sander, then 3m velcro'd it to the box. it still rattles, so I may take the organizer and apply some dynamat to the underside to absorb some of the vibrations...on some songs it is just so annoying.
and for the record, the P21s wax i used last week has lasted through a carwash and being covered in mud and dirt, and 4 days of rain.....still stays waxy.