It might be too late for the taillights. That work would have much easier to do while they were still loose, and you could lay them on your work surface. Then you could have used foil, or even a fine-tipped silver sharpie to add the chrome details. Now that they're installed on the model, it would be very difficult to add that detail at this point. Probably best to let it go.
And just to add on to Brett's comments... the stripes should end at the bottom of the spoiler, and not extend down any further. A small detail for sure, but like Brett said... if it's detail you're after...
BTW, keep this in mind for next time: Before you start on your next model, always do a google image search. That's where I found the pix I posted. It's fast, it's free, and you will find tons of great photos that will help you get all the details right. I never start a model until I have collected a folder full of reference images.