I finally picked up an interior kit for my SCX10 Trail Honcho. It is made by Dinky RC. Putting it together was actually easy. I had to do some trimming to get it to fit, but it works. And some of the Axial scale interior accessories fit good too, but I had to do some modifications to get the steering wheel to fit.
Of course I have some figures that I wanted to use, and they just happen to be the right size to fit.
Now I just need to take it out for a drive and see if the passengers survive.