Depends on how you want to mount the glass. I called my glass shop and they preferred to glue it in like current model vehicles, which allowed me to weld the 1" aluminum solid round stock in all four corners, making it stronger. I then had a machine shop mill a recess around the inside of the frame, leaving a recess (cut a notch less than 1/4 of the Diameter). If this isn't clear, let me know and I'll take a few pics for you.