My husband and I have had the same problem with our '97 Lariat. We keep blowing a fuse that takes out the wipers and the radio. The part is around 180 dollars from the dealership. Just ask for a GEM module-they know exactly what you are asking for. There was a recall of some kind in Nov. of 98 but I don't know details. That's all the information I could get off of an AllData site.
Anyway, the module is located on the back of the fuse block. My husband hung upside down under the dash for quite a while to get ours out. He said that you take the fuse block loose and let it hang by the wires. You have to flip the block upside down and remove two 8 or 10mm bolts and the GEM should just come off. Hope this helps.