Flip up rear sight - can I drift it?

Hello - I have a National Postal Meter M1 carbine with a flip-up rear sight. It (the M1) may not be original, but it’s close enough that I do not want to do anything that would mess it up. (I have a CMP Inland as a shooter.) The problem is that the NPM shoots several inches to the right, which is probably fine for combat, but not so great when you're trying to hit a paper target. I'm wondering if I can drift the rear sight slightly to the left without doing any damage. However, I am somewhat hesitant to do this for the following reasons: 1) On the right hand side of the rear sight base, there are two scribe marks that correspond with the right edge of the sight. In other words, it seems like the sight was already adjusted to the right at some point. 2) On the left-hand side, right where the sight is dovetailed into the base, there seems to be some type of tiny piece of metal between the base and the front corner of the sight, almost like it may be some type of attempt at staking the sight. It looks like a tiny fragment of a nail or something, or maybe it’s just some staking. I don't want to hammer on the sight if it's been staked in place. I’m attaching a few photos which may help, although I know they are not very detailed. Anyone have any ideas or advice? Does this sight look staked, and how dangerous is it to try to tap it to the left – could I loosen it permanently? Thanks

This may sound silly, but does the barrel appear to be straight?
Many are slightly bent without the owners knowing it.
Rule that out first.
If barrel is straight, the index marks on the right aren't doing you any good at this point. More than likely after indexing, the slight chisel type staking done on the frt left dovetail moved the site back to the right a bit.
You don't mention how far away your shooting when hitting to the right.
If you do decide to drift the site to the left, a little at a time is best.
Nice and easy, trying it down range between each fine adjustment. The dovetails narrow as you move to the left.
Odds are you just need a fine tweak. If it does loosen the site after getting it adjusted, you can always peen the edge of the dovetail slightly, or like many do squirt a little loc-tite under the site's base.

Good Luck,
Charlie-painter777

use a proper drift please, or a chunk of hard nylon. Please dont smack it with a center punch like one of the previous owners of my S'G' did.

I use brass punches against steel,It may leave a yellow mark but it ruds off. Brass doesn't mark or deform the part.

I also use brass puches/drifts and a brass hammer.

Hardwood dowel, trim hammer (gently).....Frank

couple things..
if you move the sight...
left to right out, right to left in, dont push it to far left, youll ruin the dovetail.
second.
id almost bet, that barrel is out of index, or bent..common with Carbines.
heres how you can check index..
first, dont trust the wintess marks, they are known to be off.
remove the rifle from the stock, remove the trigger housing.
with the receiver upsided down, put in a soft jawed vice, a shop rag in the jaws should work ok, just dont clamp it down super tight.
take a small bubble level, accross the bottom flat of the reciever, make sure its level.
then check the machine flat of the barrel just ahead of the reciever face, it should be exactly the same..if its not, its out of index.
if it is, chances are the barrel may have a slight bend,
if its bent, contact me, ill walk you through how to straighten it.