How do you replace clucth slave cylinder on a Mazda 2002 b2300?

first things first go and get a "one man brake bleed kit" usualy a tube with a one way valve on the end.

now get under the car with with your new clutch slave.

undo the flange nut on the tube going to the cylinder and pull it off. have a plug of some sort ready to block it best you can

undo the bolt/bolts retaining the cylinder to the bell housing.

throw the old cylinder away. and bolt the new one onto the bell housing. making sure the pin sits snugly in the lever. connect the flange nut back on.

connect the "bleed kit" the bleed valve firmly (the little nipple thing with the 10mm nut) and then loosen the valve slightly.

in the engine bay take the lid off the clutch fluid reservoir and fill it up

the depress the clutch pedal a few times while looking under the car to see if the flange bolt is leaking on the new cylinder. continue to depress the pedal a few time making sure you keep topping up the fluid in the reservoir (if it gets too low you start sucking air into the lines)

now you just keep doing this until the bleed line has no bubbles in it.

tighten the valve back up and remove the bleed line.

check the reservoir is at the correct level and that the clutch travel is smooth and firm. if it isn't you still have air in the line so you will need to continue to bleed the air out by connecting the kit back up loosening the valve and pressing the pedal till no air is in the line and tightening the valve back up

never reuse old clutch or brake fluid

and never over tighten the valve