I forgot to mention JB Dams!! You can make a form out of masking tape (sorta like a concrete form... sorta) and pour/ooze/gob the JB into it. As the JB just starts to harden you can carefully position/work it where you want it. My previous experience with quite thin AL cans prompted the use of the JB Dams as the vibrations litterally shook them apart.
If the pieces don't have a good interference fit, use more JB!

Good Luck!