Holes for the Laser head were tapped with an M8 x 0.7mm tap and an M8 x 1.25mm tap. The collimation tube head was tapped using the same method. On the collimation tube assembly, the tapped head is an 6mm telescope eye piece with the lenses removed, so I just drilled the hole out about 1mm wider in diameter and taped it out to 8mm to fit the connector.

You may notice on the collimation head picture that, there is a double FC/PC connector on both sides, this is accomplished simply using the shorter ends of the connectors and screwing them in end to end. I didn't have to do this, but I wanted the beam as close to the lens as possible to reduce any chance of internal reflections.