I'll bet that a limited production run of AMG diesels in the US would yield good sales results. If an OM603 or an OM606 can be tuned to over 400 HP, then it should be possible to tune your AMG version to over 450 HP. Bigger turbo, bigger intercooler, computer mods should be able to get you there. I'm not very knowledgable on the commonrail setup, but larger fuel injectors may be required.

This video is already floating around on this forum, but here it is again... because it's so good.

http://www.saunalahti.fi/~hecekiel/dieselboost_demo.mpg

The red one is an OM603, the black one an OM606 (429 HP).