Should be able to do so. May want to load the two front ones so the tails are stuffed into the vee and pulled together. We've had four in a 20 footer more than once though only one was a 162. The others were 153s and 151s, but we didin't even have to worry about pulling tails together in the vee.
Have the same trailer you are listing the triton 20 foot and just did 2 163 pro's side by side with a 154 summit and a 154 pro behind the other no problem. You just have to snug the fronts under the snow flaps a little ways.