Like you thought. One side of those terminals should have some space to insert a pick or tiny flat screw driver. Push the wire into the block from the engine side, insert pick on the terminal side and it should come out easily. I just cut the unused wires leaving ample wire ( if I need to use it down the road) then stuck them in a piece of wire loom that goes nowhere on the firewall. I didn’t want to remove the pins and leave a hole in the connecting block. I had 4 wires that were unused in total after removing the factory tbi harness and installing a PF4 FI. This was on an 87.
