Yup, the resistor IS mounted INSIDE the housing. Thus Don's recommendation to install a new blower motor while you are in there.

My 1986 blows only on #3 or #4 also, and I think it's because the resistor has partially failed. I am considering mounting a "new" resistor outside the blower box somewhere, and routing the wires from the fan switch to that one. After all, the motor itself has only two wires, red for hot and black for ground.

So far, I have the resistor but the job hasn't hit #1 on the list yet. And, I haven't determined a good mounting location. The dang thing gets hot, that's why they put it in there with all that air blowing around.

Good Luck,

Bob

:>)