72Cuda340, I'd assume you have had the car for a while and personally had the 340 engine installed at some point. If you purchased it already restored, then please make sure you have checked the engine block to see if it really is a 340 in there.
I don't want to sound mean or anything, but if you haven't personally confirmed the engine is a 340 in the car, someone could have easily badged it as a 340 when it's really a 318 or 360.
Again, best of luck with the sale and I'll be sure to see what it brings.