I put the shoulder harness portion on the floor behind the front seats. I just tucked them under the seat if I had rear passengers. As I mentioned earlier, I'm sure the anchors for the tail straps will stick up out of the rear seats a bit.
The quick fits would be much nicer. But if you hardly ever carry rear passengers or just put a car seat in the back, then the Ralleye's will work.
For adults and grown children, I would imagine that it would become a minor nuisance for most.
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