First of all the sender will need to match the scale of your gauge. Most gauges will come with a suitable sensor if its a digital one
Secondly you need a way of plumbing it in to the engine. There isn't simply a spare hole to just screw that 1/8 NPT fitting in to. You'll need a T or Y fitting to tap in to the oil pressure switch location, and be sure to check what thread the car * standard pressure switch uses as it may not be 1/8 NPT.