Initial statement wrote:A Haemonculus Ancient CAN take 2 scissorhands. A haemonculous Ancient with 2 scissor hands gets a total of 7 attacks. Let me explain.

The Haemonculous has standard, a pistol and combat weapon.
It does NOT exchange either for the scissor hands (think Djinn blade)
It CAN take 2 scissor hands (it's allowed to take 2 pieces of Arcane Wargear, which scissor hands are listed under)
Scissor hands CAN stack with regular close combat weapons, it's is described as such in the wargear profile.

The attacks are calculated the following way:

3 base, Scissorhand1 + Pistol (Total 2A), Scissorhand 2 + CCW (total 2A) = 7 attacks @ WS5, 3+ wounding

And YES. A Haemonculous does have 4 arms, clearly, you have not seen a Haemonculous lately

Retort wrote:Sure, if you can find the section in the rulebook that covers a special weapon, another special weapon, a close combat weapon and another close combat weapon it does.......

Further explanation wrote:Why would that be necessary at all?

Instead you have to refer Page 37 of the Rulebook, calculating number of attacks

Note the second bullet point, it indicates that models can have more than 2 weapons.
Note the third bullet point

Codex > Rulebook,

Scissorhands specifically trump the second bullet point in regards to no gaining extra attacks, where a scissorhand w/ ccw still pumps out 2A, thus 2 Scissorhands w/ 2 CCW pumps out additional 4A.

Page 42 about weapons only describes how you use close combat weapons and what they can and can't be combined with, IE PF + Pistol = no bonus Attack, or PW + Pistol = +1A, etc. Additionally a model with 2 scissorhands is not using 2 different special weapons, thus doesn't need to choose which one to use, their both scissorhands.