Yep you have a late E21 not an E30. That engine is an M10B18 and yep its EFI.
I dont have much M10 experience, but the CPS should be located on the front of the engine pointing at the harmonic balencer and crank pulley setup. however on some of the older BMW engines its on the back of the engine and uses the flywheel as the reference point. have a look at the front of your engine and if you see a disk with teeth in it, it will be on the front somewhere.