I just picked up a custom Mauser Modelo Argentino 1909, and I don't know a thing about the many Mauser 98 variations. I am assuming the 1909 is a good receiver to use for a custom build. Am I right?

The receiver is marked, "DEUTSCHE WAFFEN-UND" and "MUNITIONSFABRIKEN BERLIN". Were all the Argentino 1909s made in Berlin?

Problem #1. The safety is on the wrong side! Is there an easy way to reverse it without having to go to a gunsmith?

Problem #2. It's chambered in 7mm Rem Mag, and I'd much rather have a 7x57, .280 or .280AI. I have a 7x57 Mauser barrel in the closet - can I just pull the 7RM barrel, replace it with the 7x57 and expect it to feed without a problem? I'm vaguely guessing that the builder might have had to work on the feed rails to make the 7RM feed.

Pic of the safety:
[Linked Image]

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