How come ive only just come across this thread?/
Great job on the touch ups!!!
Just a small tip - when doing circular black lines - always use a compass with a very fine tip black marker inserted. Most of the time there is a hole right in the centre where a bumper goes etc ( as you well know!). I tape my paint jar lid over this and find centre of the circle. Draw the outer line of the black circle, then move the compass in slightly and draw inner line.
You can then paint and fill the full width of the broken line, the pen line gives you a guide for your hand as it is impossible to draw a perfect circle - even harder with a paint brush as pressure differences will give different widths.
Once youve filled the 2 lines, it looks spot on as you have a smooth edge to the line for the eye to concentrate on.
Bloody top job though - fantastic rebuild and restore