There are a number of places along this side of the engine to fill the oil galley and oil pump...

The oil filter connection is what I use, but you can use the port for the oil gauge or either of the plugged ports that you see in line with the oil filter port and oil gauge port.
I disconnect the oil line at the side of the stock filter, rig up a filler hose, then pump oil until I hear it draining out the oil pick up.