I have an RSA adjustable trigger in mine. I had to modify it slightly for clearance with the bolt carrier.
keep in mind that the trigger will still be considered an imported part so plan your 922 parts accordingly.I simply took the stock saiga trigger on my 308 and removed the stok spot welded trigger from the f.c.g. and then cut a trigger from an old romy f.c.g. then weld the romy to the saiga with 5 minutes of clean up with a belt sander it looks factory and works perfect.
Dude mine has a shepards crook in it like any other ak would have. don't beat it up if you have'nt removed it could warp the receiver or ruin the pins. Also no welding is required if you don't drill through the receiver, you just need a little filing. I drilled a hole through the trigger guard and in the receiver to mount the trigger guard with a left over rivet from a parts kit.