Since your YJ is a 1990 it should be Throttle Body Injection (TBI) from the factory. This is a proprietary unit that cannot be swapped or replaced. You basically have one big injector that is mounted inside of the throttle body before the butterfly valve, not 4 separate injectors like 1991-1995 2.5L YJ's.
My 5.2L Build thread
-1989 Jeep Wrangler 2.5L, soon to be 5.2L
-1996 Jeep Grand Cherokar 5.2L, donor and rainy day driver
-2004 Kawasaki KLR650 sunny day driver
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