Arduino 3.2" TFT Touchscreen Mega mirrored/reversed - Car LCD gauge project

I haven't used shields before.
Why do I need a shield?

"Regarding the 40-pin TFT and the 40-pin Adapter Shield. You can access A8-A14, D8-D13, D14-D21 with the Adapter Shield in place. e.g. with some angle male-header strip."

I'm making a LCD car display, for now, to read off oil temperature and pressure sensors. I need to ground the Mega Board to my car's metal body.
All of the grounds are taken by the LCD Shield.
So, that's not an option.

I guess using the 3.2" Display is out the window, unless I'm able to map the pins via wires.
Directly connecting the 2.8" Display to the Mega board, there's still 1 ground left free to use.

Regards to the angle male header strips, is it recommended to manually bend vertical male header strips?

Thanks.