The SCAR and FNC share the same internals on the trigger
Anyone ever gotten the Geissele to fit in it?
Thanks

I haven't seen Geissele make or offer any trigger groups made for the FNH FNC. I wouldn't try something stupid like buying a Geissele SSA-E trigger group made for an AR15 and try jamming it into an FNC. What's the point? FNC's sell for about $3,000 now a days, and there is a limited supply of them that were imported into the US. I'd leave the rifle alone or at least use OEM parts for the operating system. If I was to do anything to modify one, I would buy a registered auto sear and have a reputable Title II gunsmith install it, once BATFE approved the transfer. As far as the FN SCAR and the FNC, how do you know that the trigger groups are the same?

OP:
I might have some free time this week end and give that a try...…. it might very well work.

I guess I'll ask, do you have either rifle?
Because what the OP is asking about is obvious if you own either or both and look at them.

OP:
I did look but Sorry, the Geissele trigger I have is in my 17, not 16.
But looking at the 17 and FNC..... there might be issues.
ie. The FNC has a separate spring behind the trigger which is held by the pistol grip and while the retaining pins seem to be the same size, some are rotated 180.
Also the hammer in the FNC is a straight post sticking up (for lack of a better description) while both the original 16 and Geissele have a dog-leg to them.  
So you might have some compatibility issues......