Long and difficult one...

[Brian]

Local SA knife collector posted this on FB, and I am intrigued by it, but have no clue at all what it says. Can only get a few kanji, nothing leading to a solution.
Any of the helpful experts here able to solve this mystery? It's not his, but a friend's. Hoping to take a look at it. Gives me gimei vibes, but you never knw.

 

[SteveM]

於武州大和大掾国武　Oite Bushū Yamato Daijō Kunitake
南山祝長寿 Minamiyama Iwai Chōjū
百戦不殆  Hyakusen Ayaukarazu

慶應三卯歳五月二日為出生 Keiō san usagi toshi gogatsu futsuka -  tame shussei
生以首百歳二ツ胴落 (unclear) futatsu-dō otosu

 

Seems to be a gift on the occasion of someone's 100th birthday. 

The date is Keiō 3 (1867). The recipient is Minamiyama. Chōjū means long life, and the phrase "Hyakusen Ayaukarazu" means One-hundred battles, no dangers. Its a phrase from Sun Tzu. The futatsu-dō is clear enough, but I can't get the bit in between. It seems to be another allusion to 100 years, but I can't make out the first bit.  

[Brian]

You are a National Treasure Steve
Thank you so much. You constantly amaze me with your abilities and efforts you are willing to spend to help others. Domo arigato!

[Brian]

Sorry to return to this subject, but this sword popped up again here, and I may see what he wants for it.
My question regards the cutting test. Without a tester name, does this test have any legitimacy and any added interest? Usually there would be more to the test than a single mention, or not?

@SteveM

[Infinite_Wisdumb]

good luck Brian!  Sword seems to have a cool story behind it!

[SteveM]

Yes, usually the cutter's name is part of the saidan-mei, but not on this one, unless I've misread a name as something else. There are two bits that I didn't quite understand (為出生、以首)  but they don't look like names. Still, it looks like a legitimate dedication to me. 1867 would have been at the very tail end of the cutting tests. Could be the tester didn't want any attention drawn to himself. Or, it could be the people presenting it to Mr. Minamiyama didn't want to upstage him, and wanted only his name on it. But those are just wild guesses. 

[Brian]

Wondering if perhaps @Nobody san or @k morita san are able to fill in those missing kanji?
 

[Nobody]

Those missing kanji are 為出生 (as SteveM reads) and 以有, I think.

However, I cannot understand the whole context.

 

[Brian]

Thank you both. I guess it will have to remain a mystery. I wonder if that would cause suspicions of gimei or just a meaning lost in time.