......I am very suprised that David at Minto did not think of that. Not very professional in my opinion.
Should be simple fix if you can separate the lens from it's housing.
Just get a piece of thin alloy sheet that's easy to cut and cut a piece that follows the contour of the housing and with some clear Silastic glue it in place.
If you are not sure what i am talking about just look inside a tail light of a common Camry or any model with long combination lights and you will see.
If no luck bring your tail lights to me and i will fix'em up for you.
Cheers, Chris.