Which battery??

Hi guys,
For a couple of years now I've sworn by Caterpillar batteries in all my cars. There's amazing quality, 40% cheaper, and the place is right up the road. after measuring the battery tray and available space in my 67 Cuda, it looks like i have an area of 7x10x7;

1. does this sound correct?
2. What battery size do you guys have?
3. What's a good quality battery that will fit?

Thanks in advance.