Cams on tender trucks?

[tbdanny]

Hi,

I'm considering installing DCC & sound into a brass steamer.  I've already installed the tender-locomotive connection with a plug & socket, and forgot to leave (i.e. cut off) a spare wire for the cam input.  I'm thinking of putting the cam on one of the tender truck wheels instead, and I was wondering if 

a) Has anyone done this before?
b) Is it a good idea?

Thanks in advance,

tbdanny