The 68 is a funny code the maker used. They would stamp the last 2 digits of the serial number on the outside of the sideplate, then stamp the first 2 digits PLUS 1 on the inside. They only did that for certain years, and I'm not sure that it was always done during those years.
Try to get us some better pictures, because that first photo makes me think you have a good original Luger.
dju

Thx, I will get more picture posted

In that year, the inside of the side plate will have the first one or two digits of the serial number plus one. Your serial is 6729? so the plate should have "68" inside and "29" outside. One plate in 10,000 matches a Luger.

Marc

So this may be the original plate? Or it's normal for a forced match?

Yes, if the inside of the plate is stamped with "68" this would be the original sideplate.

Any idea why that was done? What would be the logic behind doing that if the outside was stamped with the original last two digits of the serial number?

Not a clue! :confused: I have always wondered that myself, but I have seen enough byf made Lugers to know that this rule applies in this instance. While there are always "exceptions", and all general statements are false including this one...IF there is no "68" stamped inside this sideplate, it is not likely the original sideplate to this Luger.:order:

Bryon,

John is right, thats the rule BUT there are exceptions AND very few sideplates seems to match guns that have been used on all European battlefields.

Rgds

Sergio