Front Passenger Seatbelt Buckle

[Rotary Potato]

I had the dogs in the car today, and had to plug their doggy seatbelts into the car. The one in the front passenger seat is now jammed in there & won't release.

How much of a pain in the backside is this going to be?

My plan would be to take the buckle out. I'm guessing the seat has to come out? How is it held in?

Also ... does anyone happen to have a spare kicking about? It'd probably be quicker to just swap the whole buckle unit and then work out how to extract the dog's seatbelt from the old buckle with no time pressure.