I think garbage disposals should be outlawed but as for the button from what I have seen they seems to go where ever it is convienent for you to use.

I think I’d prefer it off to the side. Can you mock it up with a piece of cardboard? Love the Tara! Share pics when it’s done ;-)

I put mine off to one side (faucet in the center, seltzer tap to the left, disposal button to the right). But my sink is only 29" wide so I couldn't fit the button in between the two supplies. Maybe if your sink is really large it would work better to have the disposal in the middle.

Disposal button should be to the side.

Air switch for disposal should be off to the side not directly under or close to the faucet handle. You don’t want water dripping from hands when they use the faucet handle to be dripping directly onto the air switch time and time again.

This is good:

This layout has the air button for the garbage disposal to one side