Put machine on flat surface with lots of room at the ends for removal of bar
Depending on which needle (or needles), you want to remove, pull out the sponge bar far enough to remove the needles. Remove old sponge bar taking note of sponge bar position (metal side up) and (length and width of sponge bar. (if you are not sure where the sponge bar is, look in the back of your manual and it will tell you how to remove needles and show you the location of your sponge bar)
First, Make sure all the latches are closed.
Pull the needles all the way forward towards the front of the knitting machine (D position)
Tip them down in the front enough so they clear the back of the needle guide slots. (some machines require that you bend the needle slightly to clear the back of the machine - be careful, a little bit is good - a lot is not)
Raise the needle in the back and pull up and towards the back - they should pull clear of the needle guide slot.
To replace needles, simply reverse the process.