That's assuming you're trying to fit an Amiga double density (880KB) drive and not a PC or an Amiga HD (1.76MB) one. If you want to fit an Amiga HD drive you'll need KS 2.04 or higher I think, but I could be wrong. KS 3.0 should be ok anyway.
If you're trying to fit a PC drive, you'll need a Catweasel card to use it properly. Otherwise it might work as a DD drive (880KB) with some jiggery-pokery but you will never get more than 880KB at best.
