I use the Boatloader for my 13' 92# Predator XL and it works like a charm. X2 on the advice above with angling and have some side protection for the car to avoid scratches. Doesn't take much practice to get it figured out and then it's a breeze.
I also use the technique technique below just to be sure that the yak does not slip off when loading. It takes less than a minute and is worth it for the reduced worries.
http://enviroyak.blogspot.com/2012/0...wind-with.html