Mattman, this instructions are from the Sharp's service manual:
[Lenses cleaning
Agent:
Change the mixture ratio of alcohol and ether depending on ambient temperatures. Make sure that the liquid evaporates from the lens surface immediately after you rub it: This is the best ratio. The more ether is used, the quicker the liquid evaporates.
Method:
Use well-washed bleached cotton or cleaning paper available on the market. Wipe the surface of the lens rom the center outward to collect dust. Be careful not to rub the coated surface too strong.
Reflector cleaning:
Never rub the reflector strongly because its surface has been has been deposit-coated. Use some alcohol first and then wipe with dry cloth if the surface is slightly dirty.
The picture quality is greatly affected if both sides of the LCD unit and the LCD side of the field lenses are dirty.
Pay enough attention to these surface.]
Good luck and be careful!
Federico