Hi Carl
There are 3 chromed crosshead screws spaced 120degs apart around the rear end of the tube where the original white focuser unit is attached
You'll have to remove these screws out totally and then pull out the original focuser and insert the new MoonLite one and use the 3 new stainless steel ones supplied by MoonlLite - it's that simple!
Couldn't go wrong with choosing the ML for sure!!
HTH
Cheers
Bill