You want to put it within 7" or so of the centerline with 5-6 FEET of unobstructed hull in front of it. PP has all kinds of instructions, these are from my site when I did it on my direct drive Toyota. You will need to find the right spot on your hull, make sure it is not on top of a trailer bunk. I put mine in the back in the Vdrive location, pics are included.
PP is the best money you will ever spend. I'd rather ride behind an IO with perfect pass than a SANTE with a crappy driver.