Have you checked the blower switch in the dash. It is easy
to get to and replace if bad. Grab the blower knob and
rotate with pliers (with jaws protected with rag) and pull
switch knob towards you. Carefully pry off trimplate and
remove switch and check. Its been so long since I did this,
cannot remember if I took radio out part way to do this,
but this should give you an idea how to do this. I believe this took me about 45-50 minutes to replace switch.
Hope this helps,