Yep, if you loosen the jamb nuts on that steering (clamp) block, the steering tube will slide fore or aft while you hold the rudder straight and turn the wheel 180 degrees. Looks like you're near the end of your adjustment, so turn the wheel the direction that moves the steering tube aft in the steering block to better center the threaded section. Then lock down the jamb nuts in the new position. This will give you a straight rudder with the steering wheel right side up. Unfortunately, this method will also give you 1/2 turn difference (or is it 1/4 if you split the difference?) in rudder throw from one direction to the other. Probably not that big a deal.
Otherwise you'll have to pull the cable from the helm & re-thread as previously stated to get the keyway just right.