Orval Fairbairn wrote:

(snipped)
You should note that I specified STRUCTURAL aluminum. Yes, nonstructural
parts are made for other reasons and have a places for other grades of
aluminum.

BTW, Zenith also uses pop rivets rather than driven rivets, so they
should not be used as an example.

6061-T6 is so structural aluminum.
You _can_ even get it "clad" if you got the bucks.

And the Zenith rivet technique is quite fascinating.

They start off with countersunk head steel cored rivets and use a
modified nose piece in the rivet gun to form a domed head when the
rivet is pulled. The head gets work hardended furing forming.

It's a very sound rivet approaching driven rivets in strength.