1. dipswitch on the main motherboard
2. No.
most coindoors make it easy to switch coin mechs. you usually only have to unscrew 2 screws to slide the old mech out, and then you just put the appropriate mech in it's place, and screw back down. most coin mechs are the exact same size, so replacement is straightforeward. now there are exceptions, but they are few and far between.