Two months after seeking a nearly 10 percent increase in premium rates for a low-income health insurance product, Highmark Inc. is pulling back on that request. Instead, the Pittsburgh insurer will ask for a 4.9 percent increase to the monthly cost of Special Care, the lower-cost, lower-income "guaranteed issue" plan offered by each of the state's Blue Cross Blue Shield insurers. The plan, which costs about $162 a month in this region for an individual, became the best available option for many of the area's working poor when the state legislature and Gov. Tom Corbett declined to continue funding the state's popular adultBasic health insurance. The state's policy cost $36 a month for an individual, but was not available after February.