Thanks for your opinions and advice on the '88 300 SEL. I negotiated the price down a tad and went ahead and purchased. Turned out the A/C just needed a freon charge. Now I just need to put in a CD player... and clean up the wheels, and touch up the leather a bit (leatherique arrived today). So when all said and done, I will have put about $1100 into her, but it's still worth it as I love the car. Yeah, that 6-cylinder isn't going to beat anyone off the line, but that's not a priority for me anyway. She has just 96k with full maintenance history to back it up, so I'm hoping to drive her for many years to come.