How to delete Mac OS installers from list?

Hi - I want to use OpenCore Legacy Patcher to install a newer macOS version on an old Macbook Pro A1278 - when I click on Create macOS installer > Use existing macOS installer, there is a list with Sonoma and Seqouia as the 2 versions I have downloaded. I want to use Sonoma for now as a test as I only have a 16gb USB - Sonoma wont fit. To avoid confusion if I leave this and come back, how do I remove Sonoma from both the list, and the files downloaded from the disk?

Thanks!