Thingiverse part:https://www.thingiverse.com/thing:3154398

I made a completely new bracket to fit my ratrig vcore 3 and also filled in some gaps in the original part. I then added a new servo in Klipper and added a macro to run the cleaning. The macro may need to be adjusted for the cleaning pattern and the z height to match your nozzle height.

servo setup in printer.cfg:

[servo Cleaner_Brush]
pin: PD2
maximum_servo_angle: 180
minimum_pulse_width: 0.0005
maximum_pulse_width: 0.0025

Macro:

[gcode_macro CLEAN_NOZZLE]
gcode:
 #save current state
 SAVE_GCODE_STATE NAME=pre_nozzle_clean
 maybe_home
 # Absolute positioning
 G90 
 #check if z > 25 else move to 25 
 {% set act_z = printer.toolhead.position.z|float %}
 {% if act_z < (25) %}
   G0 Z{25} F3000
 {% endif %}
 #move x,y to 0,0
 G0 X0 Y300 F3000
 #deploy brush
 SET_SERVO SERVO=Cleaner_Brush ANGLE=180
 G0 x0 y260 F3000
 G0 x5 y300 F3000
 G0 x0 y260 F3000
 G0 x5 y300 F3000
 G0 x0 y260 F3000
 #home x and y
 G0 x0 y300 F3000
 #stow brush
 SET_SERVO SERVO=Cleaner_Brush ANGLE=0
 #restore state
 RESTORE_GCODE_STATE NAME=pre_nozzle_clean