The upper screen is blotchy and we are unable to view it. I have bought a replacement lcd screen but would like step by step instructions on how to replace it please.
If you have not opened a DSLite before - particularly if it is the top screen - save yourself the grief and give it to a professional.
Changing the screen will cost about £25 if you provide the screen
Damage could be more expensive, including damaging the flexi on the screen if done incorrectly.
It has been done wrong MANY times.