You don't need much in the way of skill. Can you operate a drill?
1. Unscrew stock
2. Secure hammer spring arms
3. Drill out bottom-rear two recessed rivets
4. Remove internals
5. Drill out 3 trigger guard rivets
Install a bolt-on trigger guard from Carolina Shooters Supply
link
Press in 3/16" black nylon hole plugs for the bottom-rear rivet holes.
You can then install the standard US-made AK fcg parts as you're putting the old internals in (minus the saiga fcg of course). Slap on a US made stock, pistol grip, and handguard and you're done!
It was literally the easiest gun plumbing I've ever done. The hardest part was reinstalling the bolt-hold-open spring, but there's tutorials online which make it easy.
Check out the 2 videos from Carolina Shooters Supply, it's really simple.
link
ETA: I can't in good conscience recommend buying some gussied up monte carlo for your Saiga. It's an AK, it needs AK furniture. It WANTS AK furniture.