GAF <GAF> STUDYING BORG-WARNER <BOR> PLAN GAF Corp is studying an agreement under which Merrill Lynch Capital Partners will take Borg-Warner Corp private in a 4.23 billion dlr transaction, a GAF spokesman said. The spokesman had no further comment. Analysts said there was speculation GAF would make a new offer for the Chicago-based plastics and automobile parts company. Borg-Warner's stock rose 7/8 to 49-1/4, above the Merrill Lynch 48.50 dlrs per share tender offer price. Merrill Lynch Capital Partners, a unit of Merrill Lynch and Co, is tendering for 89 pct of Borg-Warner and offering a package of cash and securities for the balance of the shares. GAF had offered 46 dlrs per share previously. It holds 19.9 pct of Borg-Warner's stock.