One other thing to check.
Pull out pne of the window switches.
87-91 have connections at the switch where they can be removed, like this.
92-93 it’s part of the harness
If it’s the latter then that helps confirm your interior harnesses are 1993.
As for the engine harness, we are assuming it’s 1991 due to the lack of fuel pump relay, but I wonder if we should shelve that assumption. Look over that harness fpr a label. I agreee that it looks like the harness is from a different car based on the filth on it.
I’ll look up those connections in a bit based on a 1993 as that part number confirms a 93 dash harness and the door locks will seal the deal that the wiring inside is all original.
As to how the fuel pump is wired, I think the cut wires have something to do with that