I had a classic overheat/head gasket blow in my 240 and had to drive it back through a snowstorm-but that's far in the past! Later the chain eventually ate into the timing cover and lost coolant and cooked to death end of car

So regarding the leak down test you had-they told you it had a bad cyl and not a bad head gasket? Does that mean you have a cracked head and combustion pressure is leaking into the water jacket? I had cracked heads on 2002's and they ran fine just used a little coolant...

Replacing the head on this car would suck. I'm on the fence with it anyway and it might be better to find a nicer car than spend $'ss for GSR head...