IMHO I will be of little use when discussing Wehrmannsgewehre, as these are of little interest to me.
BTW about that fetish of collectors, matching serial numbers: It is a common misconception that a German military arm, be it a Gewehr 98 or a Luger Pistole 08, with matching serial numbers is still in the state it left the factory. This ain't so. Up to late in WW1 German military armorers got spare parts for repairs without any numbers, but they had proper number stamps. On replacing a broken or missing part they numbered the replacement to match the gun's serial number. So an Erfurt made P08 may even contain DWM made replacement parts despite matching serial numbers.