Not sure, but it's possible your angle strip is too far back. I don't believe it's supposed to lap over the rear cross sill portion that's flush with the top of the bed wood, but should be lined up with the vertical ledge just forward of that.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.