Well, after a couple of frustrating days I finally have the new toolbox fitted for the most part. The fit around the tranny tunnel was off by about 1/2". I cut off the flange, added new steel and trimmed until I had a good fit. Then I rewelded the flange in place. The back of the toolbox, where it fits to the rear floor is proud, about 1/4". Not sure how I'm going to address that. I'm done for the day. Time for a cold, adult beverage!