Rapidfire Front Shifter

[Mariner]

Trying to set up my FD on new build 2x11 XT gear train. The front Rapidfire 11 speed covers 3x and 2x with a selector marked 3x or 2x according to the Shimano Tech Document except mine does not have a selector. I think my previous one was the same but never had a problem getting it to work properly. Even switching to 3x from 2x cranks was easy once I found the packing piece in the mech.
Anyway I can’t seem to get this set up ‘tight’ so its giving me 3x movement on the shifter but staying on the 2x chainrings. It’s almost as if there is something compressing/stretching in the line. Hope its not cable stretch as these are new high spec Jagwire inners and outers. The RD is using the same cable type and not a problem. The RD dialed in properly on all gears after I reset it today.
Before I rip the whole thing off and re-install any suggestions of things to look at or try?
Anyone bought Rapidfire shifters recently and can confirm that there is no 2x 3x selector present on the front shifter please?

[Al]

Did you check the limit screws? Two little grub screws that’s set how far the mech cage will swing.

[Mariner]

Did you check the limit screws? Two little grub screws that’s set how far the mech cage will swing.

The mech is fine its the shifter that is moving beyond where it should.
There is an argument that 'given I only have two chainrings why shift to the third position' but lets not do that now.

[ScotRoutes]

Using a double with a triple shifter has been a thing like, well, forever. Just set up the limit screws accordingly.

I'm pretty sure there is no M8000 triple crankset so I can't see why Shimano would make a 3-way XT Shifter for one.

[Squirrelking]

As above just set the limit screws accordingly and you'll be fine. IIRC convention for shifter setup is top two gears on a double chainset and bottom two on a triple.

My 2x9 can "shift" up to the 3rd gear if I force it but all that means is I'm compressing the outers and stretching the life out of the cable. Obviously I don't do this but I've got on with it for years in this configuration.