Problem fixed. Made a new piece of metal the same shape as the tunnel, goes over the top and down the sides of the tunnel 1 inch, where the old gearstick hole was. MIG welded into place. (Left the old piece there, so did not have to weld over contaminated metal)

Got a friend who has a fabrication shop (who is great with alluminium to) to watch over the process. He's more than happy with my welding and will sign all of the required components off.

Only took the afternoon to complete as well.

Now need to send the pix to the engineer along with the welding certification.

Ready now for the next hurdle.