The method should work, yes. I've done this now with an Evo and Evo Shift. 3D Should be the same method. The ROMS, on the other hand, will not work. If you follow the guides, you'll get everything working but MMS. However if you go back a page or two, there's a link with how to patch CM7/CM9 ROMs to work for MMS, unless you can live without MMS. That's always an option, as well.
Edit: okay so it works somewhat. I've noticed a strange thing, though. Whenever I send a text that's more than 160 characters, it won't send. Any thoughts?
Edit, part deux: turned on split messages, all is well.
Edit three: for good measure, I tried a bunch of different apps. Go SMS can receive but not send. Handcent and stock are flawless. So I'm a happy camper.
OV: IHO based ROM
Evo Shift: CM7 patched
Wildfire S: Retired
Triumph: MIUI (Dead)
LG Optimus Elite: retired
ZTE Warp: My ROM, retired.
HTC One V: MIUI