John,

Not many people have seen the speedbrakes deployed. I do not know if they are welded shut, but a fellow pilot in Sweden told me they were never used. Just pulled a high G turn and the plane would stop. Lots of drag in that double delta at high G!
I have seen speedbrakes on a model once, Hans Blom of Sweden did a superb model for the World Masters in Austria. No pictures here I'm afraid.

Per