Yes, I would like some facts myself before I set my hair on fire.
For example, this gubment website on the topic says nothing about going after older RVs.
http://www.arb.ca.gov/msprog/onrdiesel/onrdiesel.htmThis article is also interesting as it talks about how this whole thing led to Navistar's engine problems:
http://www.motorhome.com/rv-how-to/rv-tech-tips/clearing-the-air-2010-diesel-emissions-standards/Seems they tried to approach the emissions problem fro a different direction and it did not turn out well. But this was all about future RVs, not retrofitting older DPs.