Is anyone using a 904 behind a GIII Hemi?

I am glad to hear it. I was never a transmission guy, I put them in and took them out but I ended up having to do some work on my 727 and began researching it and discovered that while not necessarily simple, it wasn't all that difficult either. That said, I never explored or spent time to understand the differences and nuances between the two. Growing up a Mopar guy, I always heard that the 904 was weak and never to use it behind anything with even moderate power; until I was at a drag strip and there was a guy there using one behind a very radical 340. When I asked him why, he said what everyone seems to be saying now "they are lighter and if built right can take whatever you throw at them".