When I brake sharply my 1988 2.8TD F75 Rocky tends to turn towards the right - this only happens on hard brakes, but it's there nevertheless - what might be the problem?

Also I just had fitted a new heater/blower motor, which currently only runs at maximum speed/off due to a failing blower resistor - anyone knows how much this replacement might cost?

Pictures of the part below:
http://img220.imagevenue.com/img.php?loc=loc596&image=38061_cont_vel02_122_596lo.jpg

http://img220.imagevenue.com/img.php?loc=loc596&image=38061_cont_vel02_122_596lo.jpg