How do I make a beamng car bigger?

How do I make the Roamer bigger? Just like the Bigran.

 

Thanks! I'l try it tomorrow!

 

Ok, the one problem I have is, I don't know where the Roamer blender file is...

 

Ok, so Ive got the roamer up, but I dont know how to increase the scale, as im a noob at blender. Also, will this replace the original Roamer?

 

Now what have I donez?

 

Ok, it's done, now where do I put the DAE file?

 

Ok, so I made the zip, but it doesn't load it. Then I click on the real Gavril Roamer, and it loads the big one. What have I done wrong?
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