Extending mass spring system to volume

Hi all,
I have just finished my mass spring on a 2D surface and it works fine. I followed on the approach given in OpenGL superbible 5th ed. whereby i have a pair of vao for position and velocities and a pair of texture buffer to help in accesses in the shader and then using transform feedback i get the mass springs fine.

I want to know how do i go about adding the third dimension. Adding the positions and velocites to the vbo should be a simple. What about transform feedback could I just update a single pos/vertex vbo like i m doing right now for the surface model. Please advice on what should be the optimum appraoch for this.

Regards,
Mobeen

Another thing is that currently the connection are passesd in as GL_RGBA32F format so i can have 4 32bit values which are sufficient for a 2D case where i have only 4 neighbors to lookup.
In 3d case, i have 6 neighbors to lookup can i use a higher format to store 6 integers? or the other way i can thnk of is to create a another buffer object for containg the other connections. Is there any other alternate.