theres 2 places it can be done on the oil filter housing, both are shown in the tutorial linked above from the other poster...... remove your passenger side wheel to get easier access to everything and be sure to use teflon tape and do not overtighten it into the housing or the housing WILL crack. use a 3/8 socket wrench so its impossible to overtorque it.

The 42 draft design piece threads in perfect as well