Hi Knarf,
Did you mean that (1) you would want to set these options in the UPCP admin or (2) would you want dropdowns on the product page that customers can set?
If you meant option #1:
I’d suggest using Custom Fields (e.g. you can create dropdown custom fields and select an options when creating a new product).
If you meant #2:
I’d suggest using the WooCommerce Product Page function (which is a Premium feature that can be enabled in Options -> WooCommerce)