Thanks Buz! I saw your post above and called a local welder who told me that welding cast aluminum won’t hold after a while and that I’m better off replacing the brackets. He didn’t sound like he wanted to deal with welding aluminum....oh well. The full driver side assembly arrived at my dealer and Im picking that up today and installing it tomorrow.I know this is probably way too late, but if you have/recovered the two small pieces that snapped off you can get them welded back on.
HOWEVER, DO NOT HAVE THEM WELD IT WHILE THE BOARDS ARE ATTACHED TO YOUR TRUCK. It can kill the electronics!!