Looking for a ultra lite

With that engine, stick to a large pop-up !

There are many many choices in the 17-19' box that would suit that truck.

Sure does. Thanks

A quick check indicates you have somewhere
between 1700 and 2000 lb payload capacity and
between 4500 and 5500 towing capacity.
The lower number is with 3.31 gears the higher with 3.55
So as a generalization look for a Travel trailer up to a maximum GVWR of 4500 with the 3.31 or 5500 with 3.55 gears,
with a tongue weight of no more than about 700.
That means a small trailer with an ultralight, maybe a 21' box, better chance you will be limited to under 19'.
Hopefully this helps.