Yeah you're right, it's a 60 degree pattern. Just brushed up on the 60 degree engines, been a while since I played with the 2.8 and 3.4 for my old Trooper.
90 degree engine with a 60 degree pattern... but called a Buick V6.
GMs mutt?! It's been a great engine for 155k miles though, other than crappy gaskets.
... and here I've been complaining about all of Fords bolt patterns.