So, yeah. Just drivers now. Or do you still have part of the enclosure and the earpads?
Either way, I can't imagine that this doesn't wreak havoc on the sound. If you have any chance to make a comparison between this mod and a stock pair of the same headphone, as well an HD600 or other neutral reference, if possible, I think you would find that this mod is less beneficial to the sound than you hear it right now.
Of course, I can't say that in absolute terms. Perhaps these really do sound better to you. But, I'd check back and forth a few times to make sure.