wccl 15

Hi all! Have a little question for You... I have W-CCL 1x15" and I want connect external box,..but..I don´t know how to make it? My amp from the back side have only a Speaker Output, but not EXternal Out, which You refer at W-websites. My CCL was made before 6 yrs..at 2000. EXternal Output is...