Traveling thru Guatemala and El Salvador

I just finish reading the State Department, warning issues about traveling to Guatemala and El Salvador. My plans to travel by car to Nicaragua in July are in the limb after reading all of the crime reported on this site to US citizens, from kidnatping to hwy robbery by sort of police officers driving look alike bikes and police cars. My plans was to enter Guatemala thru Ciudad Hidalgo and drive on CA-2 to El Salvador. Was told about some escort service, please any advise, or just take the plane and get it over with. Thanks