Yes, you will need "More beautification" and "Prop anarchy" or some other kind of anarchy that lets you place stuff on top of roads and rails. Alternately you can make a park with them placed on rail - that would eliminate the need for "More beautification"

how do you place these on the tracks? is it a mod?

@Soviet Sanvich: It's my plan to make some (and update my last oil train), so keep an eye out :)

Would it be possible to make one or two "generic" oil tankers?

fit well in the -Arabia- all in one Collection:
http://sp.zhabite.com/sharedfiles/filedetails/?id=580877762
thank you, Thumbs up