Without the benefit of a wiring diagram for it, or having the two plugs in front of me, I'll add this:

You can extract the wires from the plug housings, typically, using a very small screwdriver (a "tweaker" or jeweler's type screwdriver should work) to depress the tiny locking finger that snaps the terminals into the plastic housing.

Once each wire is out, you can snap it into the new housing in the correct location. I think I'd still snip off 6 inches of the donor car's harness to make sure I know which wire goes where. Hopefully all the colors agree between the two cars.

Another option may be to use the blue "tap-in" terminals, and keep the old plug while connecting the new plug and pigtail in parallel with them. That way if something doesn't work out, you could fairly easily return it to the old, working configuration.
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::: Rob Bareiss, New London CT ::: 92 244 ::: 90 745GL ::: 90 745T ::: 84 242DL ::: 90 745T Parts ::: Used to have : 86 244DL, 87 244DL, 91 244, 88 244GL, 88 744GLE, 82 245T, 86 244DL, 87 244DL, 88 245DL, 89 244DL!