My car doesn't have the lettering, so I'm making assumptions (my apologies). I'm assuming that the "M" is wider than most of the other letters and I'm assuming that some form of kerning was used, especially between the "T" and "A", and maybe between the "A" and "N". If kerning was not used the spacing would have made 'MUST' look like one word and 'ANG' like another. The effects of a wider M and kerning would push the T to the right of center, again assuming that the outer edges of the M and G were evenly spaced from the edges of the trunk lid.
It's strange the Assembly Manual didn't address this. They must have had a template they used on the assembly line, they didn't have the time to eyeball or measure the letter spacing horizontally or vertically.