I am new to the forum and want to thank, Indy -Weapons Guru for his series on the Kushnapup conversion. Using that information, I just finished the conversion of my Saiga 20 gauge to the bullpup configuration. The assembly manual I received only came with odd-numbered pages, no even numbered pages - which I still don't know whether just a printing SNAFU or was truly missing half the assembly instructions - but, it didn't matter with your photos and comments.
The only thing I noticed as a potential problem is the short leg of the gas adjustment plunger,it just barely (like maybe 1/64")