yeah i researched it a good bit as well as reading musibike's uzi tutorial like three times. and im right there with you wishing you could use more smg parts. the parts interchangablilty between the semi and full auto uzi is like the stock and sights and thats about it. wish i could go back in time and just register an uzi as a machinegun seeing as the semi auto bolt group cost more than an nfa tax stamp. oh btw i am building mine as a pistol until my sbr paperwork comes back.