Shadetree mechanic work at it's best there! They took that FSB down to the bare minimum too, looks like what's used on an 18" SKS to be honest:
There must be something underneath the FSB taking the place of the cleaning rod nipples that still allows attachment of the bayos using that clamp-like fixture. Bayo shank is pretty much gone too. It's a wild mod that doesn't really seem to serve much purpose. Why not just use stock hardware and leave it in the extended position?