i am attempting to wire a new timer switch onto an exsisting circut. the wiring comming from the wall box is the old cloth covered non color coded wires. the new switch has three wires, red, black and white.there is no indication that the box itself is grounded nor is there a visible ground wire comming from the box. if i use white as nuetral and black as hot can the red wire on the wall switch be cut, stripped and capped?