I just did this on an in process kit. If the Hookers are like Crow, The steel tab on the end of the strap that goes in the floor is a different shape and thickness than what comes from Vans. This causes the tab to sit too high if you use Vans pilot hole locations. You'll need to either drill a new hole in the tab if it's big enough to accommodate one or a different hole location in the structure that goes under the floor.
I think that you may have to space the two plates of the underfloor structure that the bolt hoes through a little further apart to accommodate the thicker tab as well.
Not a big job, but a 90* drill motor and a pop rivet puller with a small snout are must haves.