Mechanically to get more power you will need to put '18 barrels, pipes and carbs on it, this is being discussed on another post.
Replacing the headlight bulb will give a brighter light and is a good idea but I wouldn't add too many other lights as the powervalves need a healthy kick from the battery to run smoothly.
Not sure about a digital gauge, have you seen anything you want to use?
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it's a name, not a condition