Old fashioned pull-ups with weight
Just keep adding wieght with a belt. I was a Marine at one point they went to dead hang pull ups with no "kip" or extraneous movements for their physical fitness test, I started doing dead hang pull ups and adding weight. You will be amazed at how quickly your weights will increase, and the width and thickness you will add in your lats. Start with 10 pounds ( or 5, or 2.5, whatever) you will go up SO quickly, I did anyway. And never do a pullup again without that extra weight. It works man.