Hi Lwiddis.
Honestly I haven't taken any measurements. I was hoping someone on The forum had a g van at least up to a 95 since it's the same body style, I need/prefer pictures cuz I got to make sure that I can still fit the second battery in there when I get that done to it, that's another story but that was on the frame rail underneath the driver's seat. It was a diesel only but the majority of the holes are there to put one in. But mainly it saves me trouble if someone has one and can tell me what size the tank is gallon wise and I can figure the rest out,same with seeing what the mounts look like