I have a rifle that I would like to have a scope mount installed on.  Unfortunately, the area on the receiver that would need to be drilled, is the exact spot where the factory serial number is engraved.  For reference purposes, it is a surplus Spanish Mauser. (so little collector value to destroy)  The SN is on the left side 'bridge,' directly behind the 'large ring,' and the mount is a reproduction side-mount.

There is plenty of space all over the rest of the receiver, where I could have a duplicate SN engraved.  What are the rules for 'moving' the SN?  I would imagine (of course) that the second one would have to be engraved before the first one can be defaced.  Is there any other regulation that covers this?  Does the ATF need to be notified, and/or give permission?

I'm not sure about the ATF, but in our state, Utah, it's required to notify the Department of Public Safety before you remove or alter information on the gun. Same with adding new information.

I would imagine based on this, that he ATF would want to know as well. Though I haven't searched through their code for that info.

http://le.utah.gov/xcode/Title76/Chapter10/76-10-S522.html?v=C76-10-S522_1800010118000101

Dude, do I need to buy that thing back from you before you do something I regret? lol

The FR-8?  No, I found a local buyer - a guy who had always wanted one to hunt with - and he loves it. (I followed up)

This is an M43 in 8mm, which is a near perfect clone of the German K98.  Spanish rifles have very low collector value, because of the 'soft steel' horror stories.  I am even one to advise caution with small ring FR-7s, but regardless of one's opinion of the small rings, the large ones are every bit the equal of their German contemporaries.  Since mine is a 1954 production, I would put it above most (if not all) wartime K98s, as far as fit, finish, and quality.  Plus, 1954 was something like a year or two before the switch to semi-auto CETMEs, so the bore is perfect..  I am really not sure how such a recent production model avoided being made into an FR-8.  Maybe because the bore was so perfect?

Regardless, I want to turn this pseudo-K98 into a K98 sniper model, with a side mount.
http://www.accumounts.com/mobile/german-k98-long-side-mounts-additional-photos.html

I will mount a reproduction ZF-39, or similar, to complete the look.

Sniper K98? 

That's one of the cooler things I've heard of.

Sniper K98? 

That's one of the cooler things I've heard of.

Do a google search for them, to see pictures of what I am trying to achieve.  I would not drill a genuine K98, (unless I was rescuing/restoring a sporterized one) but the Yugos, Czechs, Turks and Spanish are all fair game.