Buy a 2” GSO single speed focuser from Agena for about $150, take out the three screws, remove the existing focuser, install the 2” and secure with the three screws ! It fits perfectly, took me about 20 minutes ! If you need some info Agena is great to supply their knowledge ! Just make sure you have the ID of the tube to match the proper size focuser !
Looking at the pix of your scope, it doesn't look like you had to add an extender to get focus with the 2" focuser. The Agena web site says one may be needed. Not??