The toolbox door is secured in place with a pin at the hinge. This pin is split at one end, one side of the split is bent outward to prevent the hinge pin from slipping out of position, as the other end is squashed flat. To remove the pin, first squeeze back together the split end, shown below.
Now, using pointed pliers, you
should be able to draw out the pin. Jiggling the door can help and I've
used some penetrating oil too.
Also remove the two rubber stops if they are present.
To remove the lock so that the door
can be prepared for paint, you will have to grind off the two rivets.
Be careful, these sit in a recess and you don't want to damage the lines
of that with your Dremel bit. Alternatively...
...you may also grind off the
squished rivets at the back, but this very rarely releases the lock from
the door. Once you have ground away the rivets, use a centre punch to
drive out the body of the rivet and the lock with fall away.
Finally, make a note of your lock
number if you do not have keys. Keys rarely come with restoration
scooters these days but they ARE available from good dealers if you can
quote the lock number. This is found on the lock face crown. You can see
below, mine is number 217.
The lock can be re-used after some serious cleaning and polishing.