Updated Review:
Juggernaut Tactical Rogue M1A bullpup conversion kit

M14 Rogue bullpup Mag changes

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With regards to M14/M1A bullpup conversions meeting the NFA overall length (OAL) requirement of 26.0"

The official measurement is taken from the end of the butt stock to the crown of the barrel. The 16.25" barrel renders an OAL of 24.50" 
Unless you want to add a 14.0 ounce, 2.0" factory butt stock spacer, the 16.25" barrel does NOT meet NFA OAL requirements in the Rogue.
Choosing an M14/M1A with an 18 or 22 inch barrel is the very BEST choice for your bullpup conversion.
An 18.0" barreled action in the Rogue renders a legal OAL of 26.25" when measured butt stock to crown.