Seems an older instruction. In the latest versions the thermistors are mounted in cartridges.
The only things besides the assembly you should do are :
- adapting the steps per mm in the configuration.h since this is a geared extruder
- adjust the Z-stop for the new nozzle position.
This is from my configuration.h :
/**
* Default Axis Steps Per Unit (steps/mm) Set to 1/16th Stepping
* Override with M92
* X, Y, Z, E0 [, E1[, E2[, E3]]]
*/
#define DEFAULT_AXIS_STEPS_PER_UNIT { 80, 80, 400, 402 }
Use around 402 for a 1.8° stepper, 804 for a 0.9° stepper.