i used a spray can paint to touch up a few rust spots on the trunk, but as i expected the colors don't match exactly. the biggest eyesore is the edges between the old and new paint.

i could repaint the whole trunk after sanding down the whole thing with a 320 grit sandpaper, but still then the trunk would clash with rest of the car.

is it possible to "blend" the edges between the old and new paint by spraying the edges with the spray can without any masking tape?? or will this make it look worse.. keep in mind I'm just looking for a decent DIY result, not a perfect pro-bodyshop job. thanks for help!