That was pretty obvious (that it had been prepared), you can see how plenty of the parts are just popped on/in and not bolted on, but that does not change the fact that it drives in and drives out and is disassembled in to it's main sub-assemblies in a ridiculously short time.
If they did the same thing having to drain fluids and so on it would likely be a lot more messy, and more risky (and a bit slower) so I can see why they didn't choose to do it that way.
Some military jeeps had air cooled engines so that the cooling could not be damaged by an impact of munitioned. Shooting out the radiator was a common tactic for disabling a vehicle.
I'm pretty sure I saw a guy lift out a large vertical rectangular object from in front of the engine, fairly early in the video. When it was put back in, he reached way down in between it and the engine, like maybe he was re-attaching the bottom hose (presumably without a hose clamp, or any fluids). But I could be wrong, I only watched that part twice, and I wasn't concentrating on the radiator.
If they did the same thing having to drain fluids and so on it would likely be a lot more messy, and more risky (and a bit slower) so I can see why they didn't choose to do it that way.