after i found out where i wanted them, I took a sawszall to them. I cut out both sides down to where it gets flat.
On the flat top, I bent the outer portion of the door over and tacked it to the inner. Then i layed the sheet metal over the top of it all and welded it 100% up and down both sides.
the tops of the inners are welded in, but the bottom is screwed on, this way i can access the inside of the door to work on the mechanism if i ever need to.
My doors are strong as hell as well. I have smashed trees up against them and even though they dent in the bottom, the top of the half doors work amazing. don't dent and keep everybody inside safe.