Looking for someone who has who has installed a different gauge cluster

Ian you've got the shop manual, the info is right there

Page 14-12 look up "instruments" see example "fuel gauge" is mapping 16C, temp is 15C

Now find those in the diagrams............

and they are on page 14-17. Notice that BOTH go through connector no CI-10

temp is wire G2--20V which means wire no. G2, it's a no. 20 gauge, and Violet

fuel is wire G4--20DBL which is wire no G4, it's also a no 20 gauge, and Dark BLue

Now find connector no. CI-10

(which I don't believe you sent me?)

Only ones I have is '74 and '76 and they are different. This is a round connector and the diagram will show all the wire colors and numbers going to the panel harness connector