Replacing models but not the bones.

[DMN666]

So i was wondering how to do this :3

Cause some models have edited bones.(Duh)
Example.
Lucario/Mewtwo

I wanted to use Mech Mewtwo but it needed to have a different bone so it can go with the PSA by  AGFanProduction.
Since its bones are normal and not fixed for the PSA....well it freezes.

How can i change the model but not the bones :\

[DrPanda]

If it's Lucario/Mewtwo then you could just hex over the vertices from one to the other.
That will keep from altering the bones.

[DMN666]

If it's Lucario/Mewtwo then you could just hex over the vertices from one to the other.
That will keep from altering the bones.

Oh its not just lucario there are other character too, im just using him as a example.

I was thinging about doing that but it would seem very long to do :/
Is thats the only way?