one end of 15" or so long rod, same size OD as the rod around which you formed the hole in the screenwire "donut" baffles. round off one end, heat it red hot with the torch, pass it thru the assembled can's baffles, to make sure that the bullet has aclear "path" thru the baffles, prior to first testfing thru the can. If have a .22 unit for the AR-15, first testfire the can with the .22. If you get a baffle strike, etc, with the .22, it aint nearly as likely to ruin all your baffles, come out thru the side of the can, etc.
Other end of rod, turn or grind down like a pencil, flatten two sides of this tapered area, and bend it into a little hooked end. To remove donut baffles from the can, just reach thru the ID hole, catch the edge of the baffle with the hook, and pull. then move the hook to the other side of the baffle, repeat the pulling effort. A shot of WD-40 into the tube, prior to pulling baffles, is a big help at this job. Firing the gun, with the "front endcap" washer and internal snapring removed, usually forces the front half of the baffles out of the can, BTW. If that's an option for your time and place, it can save some time and effort. Be careful with the buttonhook, cause it's easy to unravel the folded up, spindled, formed-to-shape screenwire "donut", and once you do so, getting it back into a usable shape is a big waste of time. You're way ahead to just make a new baffle.