[JensR]

I'm pretty sure you could use the stickers - you may not sell it as a CAT model, but for personal use, I would be surprised if Caterpillar had any power over that?!
Still, they should be proud to fly their flag from this fine model, the paint came out really well.
(I might be tempted to black-out the radiator grill? And maybe paint the wheel motors CAT yellow or black?)