The fog housings aren't that large and the wiring isn't that thick; I would be concerned about the extra heat causing issues. I have not run 80w fog lights though so I can't give first hand experience.
From Hella: Please confirm high wattage bulb compatibility with your vehicle. If not compatible the bulb may damage or overheat a headlight wiring system. HELLA’s warranty applies to bulb failure or lack of designed performance only.
A standard 9006 halogen bulb is only 55W, so if you are going to put an 80W replacement of any kind in there I would expect you to run into heat-related issues in the long-term (if not the Short-term).
Thanks for the answers. I pretty much figured that they would be too hot for the housings, and or the electrical system. Came across them in my stock of bulbs and was just curious. I must have used them in something at one time.
I think I new the answer before even asking. I think I used these bulbs in some CIBIE lights years ago. I agree that the wiring is too light for these on the current trucks, and like others have, most likely melt the lens.