Im from MN, rust will get past you sad excuse for rust proofing ... rust gets every thing eventually.. no way around it..
Im actually gettting the hell out of MN.. the winters suck.. with fuel costs its getting prohibitive to heat the house.. I have a very efficient new home and its was $500 a month to heat the house..thats propane and 2000sq foot.. next year I bet prices will be 50-75% higher..
As for cars.. get a new good battery and we use lighter weight oil in the winters.. and also plug in the cars when its gets 30 below out. other wise the oil is jello and it wont crank over.
If you dont know Minnesota winters.. i wish you luck.. they suck, and this is coming froma life long Minnesota resident..
My advise is get out while you can
