Is the seat bench fairly flat or does is angle downward a bit? Normally if the seat benches are flat like in my Sienna captains chairs and my friends Tahoe it is harder to get a nice upright install.... not impossible, just not easy peasy..... BUT i have seen some super easy fantastic upright installs in Explorers, Dodge Caravans, etc where the seats angle downward a bit..... I am jealous of the installs people can get. I have never sat in a Pacifica so no direct advise, just a little mommy observation from my experience with Radians last year when i was doing car seat juggling