Norio wrote:
Way I figure it, it should be easiest to do this with a Tremol-no: Lock the tremolo, change tuning, unlock the tremolo.
That won't work, literally nothing on the market will do that for you, the springs need to balance. You can lock the trem and tune to your new tuning, but the moment you unlock it everything will get knocked out of whack. You can lock the trem, tune to your new tuning, then tune back to your original tuning and that'll be fine, but what you're asking for is literally unachievable.