I loaded for UPS before (in NJ). The packages weren't the issue, as you could get into a rhythm and just build wall after wall in the trailer. The thing that always got me was the sorting. You have to make sure the correct Zip codes are in your trailer. If you have someone checking the Zips and leaving you to just load, it is cake. Hard labor, but mindless and body-building. Gets you in great shape too.
