You can use the switch on the fan but you will lose chuff sounds. If you are OK with two chuffs which I assume this has you can use John's Super Chuffer to split the signal. If you don't have 4 chuffs and want at least 4 chuffs you can add John's chuff generator mounted on the motor and not have to deal with the micro switch at all. You could set it for 8 articulated chuffs or get a new ERR Railsounds board for articulateds that would not have 8 equally spaced chuffs. I know it can get expensive. Thats why a few of us use the low dollar but more time consuming approach.
Pete
