Click the link (to the Equip Roster on OTOL) Metroliner Conversions and you'll see 10001 isn't there, so thats what confuses me, I wish there were some more solid evidence.
Referring to the photo I was only off by 819, which oddly enough is retired. One thing you also might note, if you go into the Amtrak Auto Gift Shop in SFA you'll notice 819 is the engine number on their merchandise as a tribute to the men who died in that engine.
I found a whole bunch more photos from Jim's sight here. Looking at the under carriage it does not appear to be from an ex-Metroliner where as the Conference Car does. Someone could check it on ARROW, it should be listed.