A conversion that was easier than at first expected. The chassis unclips from the body with two side tabs and then slides a couple of mm backwards before coming away - but you then need to unthread the long brass rods which are the connecting “wires” for picking up current from the trailing bogie. It is even more fun getting them back again. Just enough room to tuck the decoder beside the motor to make an almost invisible installation. A totally unexpected problem was an intermittent short after reassembly. This turned out to be the pickups on the trailing bogie touching one of the axles - wearing through the insulating paint and thus shorting. A bit of biro inner fixed the problem - but it did mean removing a wheel.