Waiting for my order to come in, I just thought about the process and now realize that
a D-Tuna will not work for me unless I have a dedicated drop-D guitar.
The bridge has to be fixed or anchored. Well, ALL my Strat's, SuperStrat's, & Stratocaster trem's float.
So that means useless to me since I float them.

As you would think the fine tunes are out of range if it were to be engaged with a floating bridge.
I don't want to add a 4th spring to stiffen the tension although it does mean that it is possible for someone to float and use the D-Tuna,
but it won't feel right and your techsneak suffers...
Just thinkin' out loud here so that it may help in someone's future decision's incorporating this in their build plans...