340 Heat Exhaust Shield 68-70

I don't know if this is helpful, but mine is stamped 2863599. It appears identical to the one in Barney's post #1.
That number doesn't show up in parts manuals from 1966, the first year to have sequential part numbers that high, right through 1971. Apparently another case of a Mopar part bearing a number that looks like a part number, but isn't the one assigned to that particular part.
I'm putting this information out there because you may find one being sold as 2863599 as I did, when the actual number is (P)2946105.