If you need to change your tax deduction card, you can use form RF-1102 «Application for new or changed tax card/advance tax 2011» or form RF-1209 «Application for tax deduction card for foreign citizens and others».
If you wish to change your tax deduction card to tax class 2, your spouse must not earn more than NOK 39,608 a year. In order for your application for tax class 2 to be approved, you must enclose documentation of your spouse's income/pension when you submit your income statement (tax return).