Of all stock dimensions,LOP is least critical IMO. We can and do adjust by moving the support hand back and forth every time we mount a new shotgun.
Cast and drop are more crucial in siting the eyes where they need to be.
To the OP.....
Patterning is your best friend. One can determine where the gun is shooting vs where you are looking and rectify.
I've a hunch(Which may be way off because I haven't seen you shoot) a slight shim at the bottom of the receiver/stock will aid you....