Of course, I'll just plug the trickle charger into the lighter socket, then disconnect the battery.
Reason I'm considering this, the Laguna's came with Recaro racing seats. I came into a set of leather seats from the same year Mustang, I guess from a premium optioned GT car. My Laguna has only 3400 miles on it, I'm considering fitting the leather seats and maybe starting to use the car a little more. Because of the airbags, I want to power off the car before swapping the seats.