here is the results and my opinion based on that.
Temp unit cold - 1.06 ohms stud to hex, 1.06 stud to block, 0 hex to block

Temp unit hot - .10 ohms stud to hex, .10 stud to block, 0 hex to block

I have another gauge her and a VL and hooked it up to the temp wire and gauge worked fine, tested the VL at 5 volts. When I hooked through the temp unit, gauge moved about a needle width. I checked and there are two different senders for that car, one for gauges and one for idiot lights. I have ordered a new sender for gauges and see what that does.

Fuel gauge. Again VL working. Tested wire as you suggest by splitting the block under kick panel. I tested wire from sender to block and continuity is there. Tested the ground again at the sender, working. I then tested the upper block wire to gauge and the gauge worked fine by grounding the wire. Put block back together and tested circuit through the block, working. So gauge, ground, wire and VL working so it appears the sender in the tank is the problem.

Does this compute with you as being the summary of results.