Looking For A Fix For A Broken Propane Tank Lid / Latch Catch
I would just rivet a piece of 1/8" thick aluminum stock that is the same width as the lip and buy a new over center latch to fix it close to stock.
This will work well, it will look good, and it will be cheap and easy. The aluminum stock is available at Home Depot as is the over center latch.
I would run the stock the full length of the cover.
On edit, i might use screws and nuts instead of rivets due to the possibility that the ends of the rivets might get in the way of the lid closing right.
If you use machine screws and nuts, you can trim/grind the screws flush with the nuts to minimize interference.
The fact that I am opinionated does not presuppose that I am wrong......