I'd say you have a mis cut stock. I've restocked over 200 L.c. Smith guns alone, and a raft of other stuff, and that is simply unacceptable. If you pull them together with the screws, your internal parts probably will not work properly. You need the space provided by the distance between your top and bottom tang for the gun to work properly. Unless I've misunderstood your statement, you'll honestly need to start over. Jake

It's easy for this to happen to the 44 actions. I've had the same situation with some of mine.   The metal is pretty soft.  So soft that you can cold bend the lower tang for a pistol grip, (I've done it). Because the receiver metal is so malleable, it'll be easy for you to bend it back to parallel.   Do it with some care not to bend it too far or too tightly.  Like a tin can, you can fatigue it by bending it back and forth.  But straightening it up will be no big deal.   With a wood block of the right thickness between the tangs, you could even do it with a lead or hardwood mallet.

BTW a very good (and common) modification for the 44 is to install a throughbolt for the stock, like a Ballard.  The traditional way is to weld or braze a block between the tangs where the rearmost screw goes, but there is another way that doesn't require using heat, and doesn't require so much wood to be removed, either.