Advice, tips re. removing duragal for a weld?

I'm TIG welding a Duragal door and frame with quite a few small section welds to a 65x35 perimeter frame. Any ideas, other than grinding to remove the gal coating. No problem doing ends of sections I just stand them in Hydrochloric acid for a few minutes but on the side of a long length is a different issue. I thought of the possibility of mixing up a flour paste with Hydrochloric and putting it exactly where I want it. I find the grinding messy and time consuming. Thanks