Anthony, that's a great idea with the magnets!
You could also use them to hold open the top window to the bottom of the wing.
There was no factory latch or hold for this on the original.
There have been plenty of field mods to accomplish this.
Some pretty imaginative some pretty crude.
How do I know?
That's my full size J-3 in my avitar as it sits on loan in the EAA museum in Oshkosh!
JLK