Cool concept and I appreciate the amount of versions of the content included, however I think it would be better to work on the presentation.
- The overlay interferes way too much with readability but the no overlay version is very plain. I would go for a version that includes headings and ditch both, this would be much friendlier to people using screen readers too.
- The mixture of portrait and landscape content is very frustrating when using a PDF
- I would consider a slightly different font for highlighted terms like PUNCTURE. They do use bold but there is a lot of red on the page so if you are scanning quickly to find a mechanic it is a little tricky
The blood splatters and finger prints are really cool so it would be awesome if there was a way to fade them to make the text above more readable without losing the impact