QUESTION Animation of swapping

[Kt1115]

There should be someone who try the mod from HK51. I am trying to make a car mod with some parts swapping such as wing, hood just like the HK51 did. The idea is most likely hide the second part in somewhere and scale down that, after press assigned button like ‘extra a’, then relocate it to the right position and return to normal scale/the first parts will be hidden to somewhere and scale down as well.

My question is, I use blender to create the animation about it, but fail to do so. Does anyone know how to do it and teach me? I have tried several time but in vain. Thanks a lot.

 

[Kt1115]

Updated:
I have successfully made the animation with swapping two objects in one ksanim file.
But the other problem is, when I use blender to export the animation with the gauge, I have re-opened the blender to check again, the needles are well( as photo 1, the transform and pointer to 0 are work), but when using kseditor to open the animation after open the car mod, the transform and pointer got a little bit move(as photo 2, the needle is not pointing to 0 as the middle gauge, and the needle from the right gauge changed transform.)
Does any one help how to get it fix? Thanks