From the FR2LE specs, the max line in is +2dbV (not +2dbv as you state -- careful, a dbV isn't the same as a dbv, but a dbv = a dbu).
Anyway, that is really pretty low. +2dbV = +4.2 dbu
The V2 puts out a max of 27dbu (23dbu louder than the FR2LE can take), so you'll need to run it really low.
The V2 has a minimum gain of 10db (less the -10db from the trim). I'd set the V2 at the 10db gain level, maybe the 15db gain level max.
Your km184's have a sensitivity of 15mv/Pascal (Pa = 94db SPL), so with that sensitivity and with 10db of gain from your V2, you'll clip if the sound in the room gets to 122db (perhaps less since the km184 sensitivity is measured at 1k Hz, so with a lot of low end energy you could be clipping the FR2LE at something less than 122db SPL). 122db is loud, but not out of the realm of possible for a loud band a small club really close to the stacks.
Anyway, I haven't run this rig, but from the specifications, I'd run the V2 at the minimum 10db gain, and maybe even dial that back an additional 5db using the trim knobs, and from there set your levels using the FR2LE dial.