Very little room exists for a decoder and speaker in the Roco model. For reliable running, the model necessitates fitting of a stay-alive circuit to the decoder, to overcome short power interuptions. The 8-wire harness of the decoder is shortened to about 20mm long. The stay alive comprises one, 470 microFarad 25V capacitor, 1N4007 diode and 100 ohm 0.5W resistor. Refer to the LokSound V4 decoder manual on ESU's website to follow how to wire up a stay-alive. The speaker is a Zimo Sugarcube, and possesses excellent sound reproduction capability, exceeding that of the larger ESU 16x25mm speaker. The body is first removed from the running boards by removing the radiator grille. Refit the body, taking care as there is very little room for errant fitment of parts.