need help with 1990 integra b20b swap

im swapping a jdm b20b into my 1990 integra, im using my stock obd0 harness, JG 301 cams and dual valve springs, blox intake manifold. ok but heres where i ran into a small dilema. the stock b18a has three sensors on the rear of the block. the oil pressure, water temp switch and the oil temp switch. the b20b only has a the oil pressure sensor but has the water temp switch on the thermostat bell housing. now i cant locate the oil temperature switch. does the b20b eliminate the oil temp switch? what do i do about the plug for the oil temp switch?

someone respond!