(a) The amount paid upon declarations of estimated tax under this act during any calendar year shall be allowed as a credit against the income tax otherwise imposed on the taxpayer by the “Kansas income tax act.”

(b) If the amount paid on the declaration of estimated tax during any calendar year exceeds the income tax liability of the taxpayer, any excess shall be applied to any other tax then owed the state of Kansas by such taxpayer, including fines, penalties and interest, if any, as provided by Kan. Stat. Ann. § 79-3233j, and amendments thereto, and the balance of such excess, if any, refunded to the taxpayer as provided in Kan. Stat. Ann. § 79-32,105 (c), and amendments thereto, or at the taxpayer’s option credited to the taxpayer’s declaration of estimated tax liability for the succeeding year.