In RaceDay Scoring you can use Custom Questions from RunSignup to filter a Top Finisher Category. This will allow you to create a special Top Finisher Category for a Race that only includes participants who meet a condition. 

For instance, you may have a custom question on RunSignup set up that asks "What Category are you racing in?" with responses like "Clydesdale", "Athena", etc...

Include RunSignup Question in Participant Sync

Go to the Participant Sync tab, then check the "Import Data" checkbox next to the Question you would like. Then click the green "Save Sync Settings" button.

Now you will see this information in RaceDay Scoring, and can use it in Reports/Top Finisher Categories to drive Participant Info Filters.

Set up Top Finisher Category

Navigate to the Age Groups tab, then click Set Top Finishers

Next click Add Another Band

Adjust Top Finisher Band Settings

Now we will configure the scoring settings for this Custom Top Finisher Category. For more information on the settings described below, see the associated guide How To Configure Top Finisher Categories

Name your Top Finisher Category, and select the Gender display type.

Next, open up the Participant Filters panel by clicking the header of that panel, or the dropdown arrow on the right.

Then select the Question you want to use from the Field dropdown. 

*Hint* You can type into this field to search for a specific field - I searched "Category" in this case to get "What Category are you?"

Next select the Value of the Field you would like to use for this Top Finisher Category. 

Finally click Save.