How to make vehicles float

Go into forge mode and spawn a vehicle that you have two of. Once you've spawned the vehicle set the run time minimum to never and drive it now too far away now spawn a second vehicle near the first one you spawned and set the run time minimum to ten then blow them both up, but blow up the one you spawned first second. now wait until the first one spawns and drive it not far. Now when the second one appears if you pick it up the first one will float.