I'll take a photo in the morning and see what some of the experts here can offer up, perhaps it's just normal (i didn't think much of it until now). It's too hard too explain, but I believe it's been modded in some way, the sides of the undercarriage where it would usually be a straight diagnal down is round instead of just straight like usual, and the pic I'm looking at at the moment has embossed lines on the undercarriage also. Probably makes no sense, as I said it's hard to explain
Lift up the carpet from inside the car and it looks all normal, no rust, etc.