There is a hon3 forum that discusses conversions in great detail. Basicly this is a money and labor losing hobby. It takes me about 20 hrs to convert an engine to DCC and sound. Cost for decoder and speaker $120.00. Pilot and trailing truck wheel sets usually need one wheel converted to plastic for shorts. Tenders need all wheel pickup for smooth electrical pickup and add $20.00 more for a keep alive capacitor. The pitman motors if equipt will need changing to can for DCC and cost about $ 50.00. The loco doc can help with sizing for the motor. Many of the gear boxes are weak and wear out quickly , will need changing to a nwsl. Lots of work and money , you have to be motivated to do it. Mktjames