Glad it is of help.
Getting the right connections is part of the journey. I often copy and colorize or redraw the connectors/panels whatever and have them as reference on the workbench.

With the resistance readings good, at least you know the gages are not burned out.

Its possible D cells can, and the AA batteries can't supply the power needed, even though both have the same voltage.
(The amp-hour ratings on the smaller batteries is lower. )