I didn't stamp on the tin- I stamped on cardstock and attached it to the tin.
I haven't tried spray paint- that might work better though! I used acrylic paint and it seems to chip off where the lid closes.... hmmm.
Scratch up the tin with a little sandpaper before you paint- it helps the paint stick more. I paint mine first.
Yes, I buy the altoid tins with the mints and put the mints in a candy jar
they are cheaper to buy them this way (like at walmart in a 2 pack) then the empty ones at a craft store.
I did attach one of my sets of pics to the bottom of the tin- and one I did not. I think you can do either
Hope I helped just a bit!!
Lori