Climate control car such as Fairlanes, Fairmonts and LTDs. don't have resistor packs they have a transistorised fan speed controller.
The main transistor in the fan speed controller (silver box on firewall behind the glove box) that sits in the a/c air intake duct to keep cool will have corroded and shorted stopping the fan working. Leaves and moisture get caught in the duct sit on the transistor casing and rust it away. Replacement transistor can be had from Worldwide Electronics WorldWide Electronic Components
for less than $15. The symptom of the transistor's failure is a fan that stays on high speed or stays on all the time.
The transistor is Motorola 2N5686 (Ford used to own Motorola). The box opens easily by bending the tabs and its not too hard to unsolder the transistor and replace it - just ensure the orientation is correct so you don't reverse wire it (very easy to do as it seems to fit better the wrong way around).
To prevent the transistor failing again I suggest you add a TO-3 plastic cover (Cat ZM-0004 at Jaycar, Cat H7290 at Altronics, Dick Smith have them but I can't find it in the catalogue) and /or an additional TO-3 heatsink (part number H3400 at Disk Smith, Cat number H0610 at Altronics, and HH8510 at Jaycar). These will keep the leaves away. You can also spray the transistor's outer case with circuit board lacquer or something similar for added protection.
To replace the boot strut remove the rear seat base two bolts and side cushions (another bolt on each side - one for each side cushion behind the cushions on their outer window side). These mounts sometimes break off and although they give you an extra presumably to cater for this eventuality they might both be broken off and if so you will need new ones mig welded on