"...is this what is meant by 'Minor Varients noted.'?"
This is what meant by "re-blued parts gun."
Seriously, though...the identification sheet is deficient in one respect which is important to you right now. The crucial difference in receiver marks is the difference in the proof eagle, which I have illustrated here:
An Erfurt-manufactured frame will have an inspector's mark on the front of the trigger guard:
If you go to this link
http://forum.lugerforum.com/showthre...ghlight=Erfurt you will see a profile which clearly shows the panoply of marks one expects to see on an Erfurt Luger.
Let lus know what you determine.
--Dwight