This column was originally published on RealMoney on March 14 at 1:36 p.m. EST. It's being republished as a bonus for TheStreet.com readers.The basic-industries sector began the year 8.8% overvalued and is now 16.8% overvalued, so finding bargains is no easy task. For investments in this group, I have been focusing on stocks that rate as buys with ValuEngine in subsectors such as the chemicals industry, which is 12.6% overvalued, and in the nonferrous base-metals industry, which is 8.7% overvalued. I believe that investors should be raising cash from overvalued and overbought stocks on strength up to risky levels. Investors will also want to put some cash into buy-rated, undervalued and oversold stocks on weakness down to value levels. Chemical companies Dow ( DOW), Lyondell ( LYO) and DuPont ( DD) all currently hold or have recently held buy ratings, and all have been or recently were at least 10% undervalued. The share price for each is below the 200-day simple moving average, which is a sign of technical weakness. Nonferrous base-metals companies Alcoa ( AA), Phelps Dodge ( PD) and Freeport-McMoRan Copper & Gold ( FCX) have had buy ratings with mixed valuations, and share price has been declining toward the 200-day SMAs. Make your portfolio a more potent mix by adding to chemical-stock positions on weakness.