Turns out the resistances are different between the Taco sender and the Hilux sender. When he has a full tank of gas, his gas gauge reads about half-tank. I gave him instructions on how to mount the Taco fuel gauge brain behind the Hilux fuel gauge display, which he did, but he said it made no difference. So I don't know what is going on until I go check out what is going on. (I'm limited on time for side projects at the moment)
