Now, you have appared in San Fierro. Now you have have single mode in this mission because there an accident. When you have get down from the train, Lex miss to get down. So he continue his way and promise he will meet you at Gerry place when he have a chance to get down. But you two are decided to meet at Garry place. So you need to go to Garry place and capture him.

NB : Sorry if sometime you don't understand this mission. If there are some problem in this mission just leave a comment.