I am a complete novice in the AK world and need some advise. I have a friend that has offered to sell me his MAK 90 Sporter AK 47 with the thumb hole stock. The price he is asking is very resonable. My questions are; 1. can the thumb hole stock be replaced with a traditional AK stock and pistol grip? And @. is this a particularly tricky deal to change out? Thanks. Wanna kill these ads? We can help!