Having flopped a few times, I wouldn't want those doors. What I noticed about my seatbelts is that unless you hit something with a thump, they won't hold you in. There are litle pendulums that are resisted by springs. If they overcome the spring they throw a pawl into a gear the locks the belts. All three times that I went completely over I had to hang on for dear life. I would hate to end up with an arm or leg on the other side of that gate. I do not like those at all. A cut down door I could see. Something to give you better vision.
And I agree about the welds. The door is part of the structure of the cab. It's not going to be stiff anymore.
I would toss them and work on a half door. Make a low cut in a factory door using the factory hardware. Keep the top part of the door but get rid of the window and lower the sill 6". I wouldn't want it, but it would accomplish your goal and you could make it to old age with a 4 limbs.