Actually in my Golf I have a Jegs box. Its kind of cool, the lid is held on with flip latches.
But I hope I got a dud as far as the hardware goes, because only one hold down stud was the right size, the other was smaller than 1/4-20. And none of the nuts in the pack matched the studs?!
The Taylor lid is held down by the two studs that hold the battery in place. It has a pair of nuts that hold the battery down, then another pair that hold the lid on.

1/0 is a bit overkill. I usually use 2ga. There is a surplus place up here that sells Streetwires and similar stuff for cheaper than butying wire from the welding supply.