Well its quite easy, you can either remove the floppy caddy altogether like i done as i dont use it and the space will be used with my mod , but this means u wont be able to use the floppy bezels and ull have a hole in the side of the case because of this.
Or you can just cut a section out of the floppy caddy so theres space for your card to fit. Wont take you too long, 5-10min job really.