Consider adding railcarphotos.com into your list - searching for DODX between 14000 and 14999 yielded thirteen photos, three of which are in the 144## range. I can't make out placards on one but the other two are placarded 1863 for turbine fuel. That said, my general impression is these cars may be second hand as the three cars are not similar to one another... one is 49', another 52', and the third sports a full-length walkway.
Thanks, didn't have time for that yesterday. Looked today and 3#s in the 14400-14499 range, one of which is clearly not what Athearn is trying to depict (14454 has full length top railings).
Can't make out the build dates on the other two, though both photos date to the 21st century.
14402:
https://www.railcarphotos.com/PhotoDetails.php?PhotoID=51175 The Athearn art work shows a build date of 3-70 - the Athearn model looks to be a "stand-in" for the DODX series modeled.
14488:
https://www.railcarphotos.com/PhotoDetails.php?PhotoID=20586 notes say
"JP-8 Jet Fuel"14402 & 14488 are obviously two different tanks.
Still hoping to find 1970s era photos of this # series.
I might bite the bullet and get one anyway since there are very few models of this type of tank out there for my era (1975).
Mark