Thanks to all who replied. As it turns out the car was a 300E not a 300D as the ad had stated so the reason it did not say turbo on the back is obvious. I just missed it when I looked quickly at the back as I was standing knee deep in weeds and was worried more about getting ticks on me than checking the model during the quick check-out. The seller contacted me to inform me that the ad was in fact in error and it's a gasser after all
On another note, I removed the "E300 Turbodiesel" badging on my 1998 W210 after one of the letters fell off in a car wash and like it much better without it. Each one is a peel and stick letter and I removed them using a soft popsicle stick to pry them away from the trunk lid and cleaned up the glue residue using goo-gone. I think the car is much cleaner looking "badgeless" too.