Chris,
Here are some progress shots showing the body comparisons between the Atlas and RC. They are exactly the same size. You will see that the Atlas shell has body mount posts and also mountings for the roof antenna and front/rear lighting pc boards & LED's. Underneath the cab there are cut outs for the chassis switches. The next series of photos show the trial fittings onto the Atlas chassis that now has had the front motor removed. Engine runs fine with just the rear motor and has retained the cruise function. The engine has suffered some loss of pulling power from the front engine removal. The original front headlight board will now be placed in the new headlight pod in the cab. You will see that I have since decided to use the original Atlas long rear hood and only use the RC modified cab and chop nose. By do this, I have retained some body mountings as well as antenna, rear lighting and smoke stack fixtures. It all mates up very nicely. I will have to now modify the fireman's side tool box/steps by shortening the front section. I have decided to add Atlas 2 rail fixed pilots and handrails also but for now, this project will go on the back burner. It only got to this point due to your inquiry. Thanks for getting me to figure things out.