Here's a $33,995.00 1972 Plymouth Satellite Sebring Plus for sale. Advertised as a numbers matching 400. Looking at the VIN, the motor code is "M" (400 two-barrel). The code for a 400 four-barrel would have been "P". On the video, the engine to me sounds kinda noisy and crappy under the hood, but maybe that is just because of the headers and unsilenced air cleaner. It advertises a factory tach but shows an 8000 RPM dial. My parents factory new 1971 Road Runner had a 7000 RPM tach, so I believe the 8000 version is not factory at all. Don't know if the trunk lid had that Sebring plus logo on it from the factory, obviously the header emblem is a 1971 version, which is what I will use on my '72 SSP also:
http://www.streetsideclassics.com/vehicles/1749-dfw/1972-plymouth-satellite-sebring-plus