As a side note, replacement fuel injector clips (for wiring harness) can be obtained from auto parts stores to replace broken stock clips. I got the parts from autozone:
GP Sorenson part 800-9416 Fuel Injector Connector.

I have not found an aftermarket source for oval injector clips.

More about injector impedances on 2nd generations:

1986 and 1987 model cars used low impedance(2-3 ohm) injectors. Low impedance injectors have a center notch on the plug. The wiring harness used with LI injectors integrates an injector resistor pack, wired inline between the ECU and injectors(under stock air box) to bump overall load seen at the ECU to 12-13 ohms.

1988 and later models used high impedance injectors. 1988 HI injectors have an offset notch on the plug, and all post 1988 injectors are HI with an oval plug(until 3rd generation side feed injectors which are totally different). The wiring harness on these models deleted the injector resistor pacl, carrying the 12-13 ohm load from the injectors directly to the computer.

When performing engine/wiring/injector swaps, the type of setup must be noted and kept together. This is easy as LI injectors will only plug into a harness meant for them(due to the position of the plug notch) and vice versa for HI injectors and harnesses. 88 and post 89 HI injectors and harnesses are not interchangeable.

A car that previously ran one type of setup can be changed to the other…keep the injectors and wiring harness together. The ECU will not know the difference.

It is also possible, but not necessarily recommended, to use HI injectors on a LI harness and vice versa: