Kevin Green says the S&P 500 (SPX) needs to hold the $6600 level on futures to maintain momentum. If not, he says investors could see a reversal of last week's gains. On the stock side of things, KG is watching Intel (INTC) as the chipmaker is reportedly seeking an investment from Apple (AAPL). Additionally, he's keeping an eye on Lithium Americas (LAC) following this week's surge on a potential U.S. government equity stake.