You are able to select specific op amps in the "Component Selection" section of the Filter Wizard design flow. There is a set of radio buttons ("Pick for me" and "I want to choose") that allow you to customize your op amp selection - select "I want to chose."
You will then see a list of stages in the left panel, under the "I want to choose" button. These stages can be expanded, showing the details of each stage design. These stages can be customized, allowing for selection of a specific op amp, adjustment of component values, and topology selection (when available).
You can select a new op amp for each stage by clicking "Change" in the Stage section.