I never had a baby bucket "with base"- we routinely buckled it in and unbuckled it as needed. Therefore, I saw absolutely no reason to install it in the car before it was actually needed- and in all 3 cases, I'm pretty sure we buckled the baby into the seat in the house and then fastened in the carseat with baby when we walked to the car. What on earth would be the point of installing it into the car before the birth? 
I did, however, set up the carseat ahead of time- taking it out of the box, assembling the straps on the smallest setting, and practiced buckling and unbuckling it into the car a few times and then put it away inside the house.

I did, however, set up the carseat ahead of time- taking it out of the box, assembling the straps on the smallest setting, and practiced buckling and unbuckling it into the car a few times and then put it away inside the house.











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