I 've seen your other thread about the AR20 but have you seen the response from Paul regarding Jon's comments about the vertical split action ?.
It's just the cover that comes of the side of the action for access to the trigger mech and the picatinny rail supplied bridges the action anyway, and has a built in slope to aid scope alignment.
I'm not disregarding the EV2 either, had one and eventually it worked ( reg and trigger problems) so if you did get one make sure it's been sorted, most have by now.
I shoot an AR now and it's every bit as accurate as the Styer's at our club.
Good luck in your search for a lefthanded rifle.