In addition to the disclosures required by the federal consumer credit protection act, if any, the creditor shall disclose to the customer to whom credit is extended the information required by this subchapter. With respect to every consumer credit sale payable in installments (s. 421.301 (30)) upon which no separate finance charge is stated or imposed (s. 421.301 (20)) the creditor shall make disclosures in accordance with the federal consumer credit protection act, to the extent applicable, whether or not such act requires such disclosures to be made.