Straps will just make it easier to get a grip on the battery. It still weighs a lot. Straps mostly help when dropping the battery down in the box.
I would just lift them in there, but how you go about it can make it easier. If this is a front compartment, sit yourself down on a stool, with the battery at your feet. Lift the battery up to your lap. Then shift your grasp and lift it over the lip of the compartment, and rest it on the edge of the battery box. Then shift again and drop it into the box. You should find that easier than dead lifting it all the way, up, over, and down.
Did you notice, as I have, that 67lbs is a lot more than it used to be?