Anyone with an older Aerostar. What have you done about the battery? Mine is 87.
Owners manual says group 64, which I can't find. I have installed a box from a 97. A group 65 is all I've found to properly fit the hold down in the box but then the terminals are on the wrong side. A group 24 has batteries with terminals both ways but it is too skinny for the box to hold it.

 

My 1990 model uses group 65. If the cables don't reach the terminals, you might consider getting new cables. If your 1987 model is still using the original cables, they might be due for replacement anyway.

 

just find the largest that will fit. The more cranking power the better. As far as the poles being in the wrong place, they make them both ways so just demand one with the poles in the right place or go elsewhere where they have it.

 

If you installed the battery box from a 97, group 65 is the biggest size you can fit. It is shorter but wider than most batteries so it would fit in the tight space under the Aerostar's hood.

 

I used a group 65 battery and a cable stretcher to connect the cables to the battery. I did have to splice in a short piece of wire for the ground to the body.
BTW I wasn't able to find group 65 with reversed posts.
As near as I can tell a group 65 is the only battery you can use in that box. Anything else will not be wide enough from front to back to hold down the battery.

 

There's a group 58 that will also fit that box, but it's a much smaller battery.

 

My main objective was to be able to use a readily available battery in this 87 Aerostar and the group 65 does that.
In an emergency almost any Walmart or any auto parts store will have one available.