is the serial # on the trunion or the receiver on the Romainian.
If it is on the trunion, then you can't move it.
I am building a krink using a Saiga 223 as a donor rifle.
I am having the factory saiga barrel turned down to krink specs.
Romanian as in SAR? that has the serial # on the trunion.
Check with jnewt (user on here) and ask him.
I think he was suppose to check with the ATF concerning this.
On my saiga, I never removed the trunion so I don't have a issue with the ATF.