I want a semi auto 308. I have gone back and forth about building one or just ordering one from GAP. I know they use the POF upper/lower. My question is, can you send them customer supplied components to be assembled as a GAP 10. My reason for asking is I already have a Bartlein AR contoured 30 cal barrel on order and I was considering getting in on the group buy for the Mega upper/lower set. Could I send them these components and have them chamber and assemble the rifle? Financially, its easier for me to piece a rifle together over time as opposed to shelling out 3k+ all at once.