Silverado Deep or shallow pan

How can I tell if I have the Deep or Shallow Transmission pan? Mine has a little step to the pan so I am assuming a deep pan. I have a 2000 Silverado Z71 with a towing package so I would think they would put the deep on in.

Any ideas? I want to get a filter and change the filter and fluid but don't want to have the truck sitting in pieces and have the wrong part if I don't have too.

Thanks