So I'm trying to build my own upper. I've got the barrel on, torqued it three times and I'm trying to put on the PRI forearm and get the two screws in the Swan sleeve to align with the holes on the top of the forearm, while also trying to keep the holes aligned on the side of the Swan sleeve with the rail of the flattop receiver. Does that make sense? I can only get one sets to align. Where am I messing up? I can't tighten both the front screws and back bolts of the Swan sleeve.