[Zekester]

For the vertical cuts, I clamped angle to the trailer on the inside, then layed in it and zipped it, it really sucked, you are in a box with the sparks bouncing all around...then I went outside and finished the cuts through the 1 x 1. For the long horizontal, I cut just under the plate at the corners, from the outside, then connected the two cuts by eye. This was tricky as I didn't realize that there is a double folded layer inside the trailer right here, I cut it in different places, so to make it even i dressed it back 1/2 inch, then welded in the 1/2" angle so it formed a new lip on the trailer...