Now you can start unsoldering. The process itself is very easy; however, if you do not have steady hands it may be difficult. The unsoldering should be done as quickly as possible to minimize possible heat damage. Please note, if your particular mouse does not have markings for + and – on the circuit board, you may want to investigate the position of the led. As in the picture below, the shorter lead is negative. However, this may not be applicable because the leads will be cut even with the circuit board. To find out + or – look inside the led bulb and check the filament position. The side with the shorter filament side is positive.