my guess is they will both do the job. the main loom should separate from the engine harness. really you may just need the v8 engine harness? (this the case in hx hz wb) i don;t know if there is provision for sports cluster in a standard 6 banger loom ie RPM . the bigger differences will be in trans config. ie auto column (at least on later models) has a elec kickdown and plugs that fit into the column so it won't start in gear etc.

my advice is to take the lot out of the donor. you never know what and when you may need something. I just took a loom out of WB and transferred into another of same year to find that the harness has a different plug at the a-pillar where it joins the rear section! Very cheesed off.