You most likely have the Mazda 5 speed (M5R2), which has an integral bell housing. You'll have to drop the whole transmission to get at the concentric slave cylinder which mounts over the main input shaft. Besides dropping the transmission the hardest part is actually disconnecting the line from the clutch master cylinder to the slave cylinder. I'm not sure how many miles you've got on your clutch or what shape it's in, but you might think about replacing the clutch assembly and resurfacing the flywheel while you're in there. Kill two birds with one stone...