Well, the 10.4 FIRM is up on the ISO site now, courtesy of Aurora Wright, so it's just a matter of compiling with changed offsets if you want to try out the 10.4 kernel. Functionally there should be almost zero difference, aside from NTR needing an update yet again.
This is great thanks daztsu, i will wait for @Reisyukaku to officially implement it though
Awesome that yourself and others are trying these things out