Some good & some bad news on this specific topic;
There is a guy in The Netherlands who had researched the issue of the infamous Fuel Strip vs Floater.
The Good News;
It turns out that the GS(A)'s ZFE has the capability for either the Floater or FuelStrip already built-in.
The connections to the specific pins on the ZFE for both the Floater as well as the FuelStrip are there and not, unlike the 1200RT, shared to other functions when you use one or the other.
Meaning, the same ZFE (on the GS-series) can used for either.
How it is with the specific connector to the fuel pump is a different story (3-pin versus 4-pin respectively).
From what I was told by a BMW Engineer, it was (also) to accommodate those riders who "rigorously" do adventure-riding.
If the existing wiring-harness can accommodate those two versions (read: connectors) I do not know.
One would examine the ZFE and see if these specific pins would be wired (too), for example.
But then I do not have a shop, I'm a hobbyist.
Ok, back to this fellow-Dutchman;
He created a plug-in "blackbox" for the GS(A) that would allow the ZFE for the Fuel-Strip (4-pin connector) to be hooked up to a Floater.
Because, kudos for him, he found out that replacing the existing Fuel Strip on the existing(!) Fuel Pump with the Floater mechanics(!) is quite a simple task, on the GS(A).
All the mechanics, mounting-points etc, are there, it is just a matter of removing the Fuel Strip and clicking-on the Floater mechanism.
Rather then trying to fool around with the ZFE wiring, his black-box then converts the signal from the (new) Floater into a Fuel Strip-type signal that the ZFE would understand.
He has been working on this for several years, but is small-scale.
Main issue is the 4-pin male connector, apparently not an easy connector to come by or every expensive.
So he 3D printed (amongst other techniques) that connector himself.
And that solution has been working quite well, he sold them to many GS(A) users who "converted" from Fuel Strip to the Floater successfully.
I'm currently investigating (read: mock-up connecting a Floater) to a R1200RT.
There it is a wee bit more elaborate;
The 1200RT Fuel Pump is an either-version; or for the Fuel Strip or for the Floater, and not "prepared" for retro-fitting the other version.
However, see my previous response, I had already obtained a R1200RT 2010 Fuel Pump which contained the Floater.
So, when a R1200RT has the Fuel Strip and you want the Floater, it would be a matter of replacing the (complete) Fuel Pump assembly. And his black-box (for the GS).
He & I both expect this should work electronically, read, the connection(s).
Which I will try to do later, chemo's are a bitch when you want to do intricate work.
I will update this thread once done.
Then the Bad News;
He decided to cease operation for the moment because this was not enough to make a living from and it interferes with his regular job.
He is currently looking for somebody to take over the operation, the tools and intellectual properties (I guess money would need to be involved) and bring it to a more production-level.
So he is currently closed down, sold all the existing stock of black-boxes and is on holiday.
Should their be more development on that arena, I will also update this thread.
I already suggested to him to go more mainstream and announce it to the world, e.g. BMW dealers, forums and such, but he was hesitant as he does not have the production-level that would potentially require it, should it really fly-off big-time.
It is unfortunate that such a good initiative boggles down for that reason, but fully understandable. If you have a regular day-job it should not interfere with that regular job.
I recall the infamous Road Rocketeer, excellent LED read-light replacement products (in my experiences) but very bad business-practices.
Maybe HexCode is interested in buying the rights to this black-box.
I will update this thread as soon as I can but wanted to share the above at least ...