Heater blower problem xasara on 51 plate?

I am trying to fix the heater motor on a Xsara 1400 coupe with air conditioning/climate control. The motor only works on full and then only intermittently. I suspect it is the heater motor blower resistor unit but it is not situated on the ducting under the glove box. I bought one of the screw in units with 3 resistors on it, as per Haynes Manual, but it is not where it is shown. My Haynes only goes up to 2000.
Does anyone know where it is on this model, how do I replace it??
My dealer would not take the resistor pack back so I have one for sale if anyone needs it.
I live in the North West let me have a phone number if interested.