Probably would interfere with closing, as I also have the cargo mat along the back which eats up another 3/8". Removing the handles and NOT replacing them may give you the room needed.I really wanted to go with the 55 since it has a lot more space than the 45 considering we are a family of 4. I also have a cargo shelf which is why i need the slide. Do you have any picture of how tight it is on the back seat and the bump with the tailgate closed? if you were to lift the fridge and put it on a 1" block you would have zero chance of closing tailgate?
I think its all worth the pain to make it work, the 55 gives a lot more room. Even though I though it was insignificant, I really love the ice maker (spiked lemonade never tasted so good) .