Everytime the bulbs have to be changed, the
paint is damaged

The result is lots of rust underneath the license-plate lights:

One of the original lights:

Sanded and painted with POR-15 (http://www.por15.dk) :

And here how to fix it,
so you never have to change bulbs again.

Modify old light to a connection point:

Use a piece of alumina and a FR4 board with 2.5mm nuts:

Mount 2 white leds with 2x1Kohm resistors (20mA) each:

This makes a new everlasting light:

Just before assembly (the transparent thing is a universal silicone lid; the rectangular piece was not used during assembly, because it was impossible to get it aligned with the holes due to the inaccessable placing of the lights):

One mounted:

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