There are two different bolt patterns for 4G64's.
You have the car version, which is a small pattern, like 4G63's.
And then you have the truck version, which is bigger, more like the Starion.
Now, these numbers aren't exact, but the 4G63 is about 11.5" or so across the bottom bolts, while the truck version is about 13" or so (give or take, it's hard to measure with the tranny and engine still in the car and I can't remember the exact numbers I came up with, but those above numbers are pretty close)