ESU Loksound 51968 21 pin adapter board with power outputs for AUX3 & AUX4
£14.06
Thus the wiring of your loco is child´s play. There are amplifiers (appr. 250mA each) for function AUX3 and AUX4 (the decoder´s logical outputs) so that ESU decoders have up to 6 available physical function outputs.