You'd just be an enabling asshole, but depending on the jurisdiction you can be charged as an accessory to suicide, which can be as weighty as accessory to homicide.
But your analogy isn't very analogous, as that's not what Kevorkian did. He hooked them up to a device he himself created (first one administered drugs, the latter one was a gas mask feeding the "patient" carbon monoxide) with the express purpose of causing death at the push of a button. He can't set up the device, hook them up, and then look all surprised when they wind up with a future in fertilizer. And in the case of the guy he was convicted of killing, he actually injected him with a killing medical cocktail.
If you want to kill yourself, don't involve someone else.