Hummm... It's an interesting adaption. The original RPD trigger group area is only about 3/8 inch deep. Not enough room to stick a hammer assembly. Any rig will, of necessity, loose the slim profile of the original pistol grip and trigger assembly, to provide the necessary room for the hammer and disconector. It's a well thought out plan, if it gets approval. The alternative is a striker type method of operation. It is do-able but messing with two springs, one for the bolt and one for the striker, would drive you mad adjusting the tension. You would end up hip deep in scrap springs. The price is a trifle optimistic, seeing the SOCOM system is only $6K and it's a real full auto. Yet there may be a market in non-NFA states. I wish him luck, but at that price I'll pass. My thresh-hold for this kind of rig is about $2200 on a good day.