One would think the base could be swapped but I agree it would be expensive to start experimenting with parts. I only know people who have the original interior like myself

 

Sell the baby, use the money for mods?

 

Or this?!?

 

Can't you take out the back seat and figure out some easy of making a bracket that attaches the base of the baby seat to the bed? Would leave enough room for a stroller. AND you can load the baby through the tailgate.

You should really talk to some safety experts before considering anything I just said though.

 

Stay with the 2 door, the only thing holding you back from getting that baby in there is you. I do it with 2 on a daily basis. That being said I have a '14. Good luck and congrats.