Originally Posted by ProStreetCamaro
This is what my 160 deck looks like
This is what the 460 deck looks like
It looks to me like all they did was slightly taper the front of the left side to aid in inside corner trimming. There's obviously a space between the front skirt and the actual baffle where no cuttting takes place, so they brought it in like they did to alllow you to get the front/left cutting edge of the left blade as close as possible to cut down on trimming that would need to be done otherwise with a trimmer.
Also, to go along with what I just said, take a look at the left front caster arms. They've also brought the new 400 arm in somewhat compared to the older unit, which alos aids with inside corner trimming.