If you are able, order a diff cover from Solid. They are the best deal on the market today for a nodular iron cover. Suggest you get it from this guy, he has great customer service and can get you nearly anything off-road related. Disclaimer; I don't know if he ships to Norway...
http://www.davesoffroadsupply.com/Solid-Axle-Industries-Ford-88-Cover_p_1331.html
If you do contact from him, tell him you got his information from Brian Kennedy in San Diego. I send him all the business I can, he is that good with customer service, and he price matches. He recently beat a manufacture's price for my neighbor from Fox and Full Traction by several hundred dollars by price matching and offering free shipping. He ate stuff to keep my business, and offered to eat something that wasn't even his fault (manufacturer defect on FOA shock reservoirs). There is a discount code from another forum, pirate10, that should give you 10% off if its still in effect. Best bet would be to email him, telling him what you want, where you live, etc., and ask what kind of price you can get.
This is how most people make their off road vehicle stronger; break stuff and replace it with that is harder to break. You are well on your way..