So are you saying that the shop built the engine and forgot to fit the valve?
In that case, simply tap the new valve into the hole where the valve is meant to be.
INSPECTION AFTER REMOVAL Oil Cooler Check oil cooler for cracks. Check oil cooler for clogging by blowing through engine coolant inlet. If necessary, replace oil cooler. Relief Valve: Check relief valve for movement, cracks and breaks by pushing the ball. If replacement is necessary, remove relief valve by prying it out with suitable tool. Install a new relief valve in place by tapping it. INSTALLATION Note the following, and install in the reverse order of removal. ● Make sure that no foreign objects are adhering to the installation planes of oil cooler and oil pan (upper). ● Align cutout on oil cooler with protrusion on oil pan (upper) side, and tighten connector bo