Which version of Poser are you using? I've been modifying some Judy clothing to fit Posette and Furrette, and even though I can re-group the .obj file to allow for the changes (no buttock groups, so that have to be shifted to thighs and hip, joint between thigh and shin at a different height), there's other stuff associated with the boning. There's a significant shift on the Z-axis, and the boning has to be adjusted relative to the clothing-mesh. (There's other differences, but I did get the Combat Pants usable with a only minor poke-through to deal with.) In Poser 5 you can fiddle with that in the setup room. I'm not sure about Poser 4. Anyway, I can see you having to tweak the boning because of similar descrepancies in the default positions of the two meshes.