Does anyone out there have a sound in house method for calibrating density and viscosity cups that they would be willing to share with me?

Here is a link for the oils and ifno you would need.
http://www.gardco.com/pages/viscosity/oils.html
As mentioned temperature is critical and recomend that the oils and cups are placed in a controled area to stabilize prior to use.

As for the actual method of calibrating the cups; obtain a copy of the specification the cups meet and you will find that it contains the Cal method and required accuracy.