Hmmm... dodge magnum with an overheating problem, and the owner still drives it? I'd put money on it that it needs new heads. My brother's '01 5.9 had a leaky radiator and he drove it across town (Fresno) to get home after work, he watched the temp gauge and it never got "in the red." He parked it and replaced the radiator soon after. Truck continued to overheat and we diagnosed the cracked heads, luckily he is handy with a wrench so it only cost ~$1,000 and a weekend for new heads.
Pass... on so many levels.