There is no "second options" depending on "first options" mod or availability in Zen Cart.

HOWEVER, if all that changes is the price of the option, you might be able to do this with just the attributes controller. Setting the products to priced by attribute, you could have a selection for widgets and wheels.

This would only work if all wheel sizes are available on all 8 widget sizes.

Each widget would be priced where its attribute is defined and the same for the wheels. Wheels could be positive or negative values.

Not unlike what you see at "Swell" Computers where one hard drive is included, another is smaller and cheaper, and another bigger and more expensive.