Search "Lionel 200 first motorized gondola". If you do an image search, you will get lots of different views.
Remember that the track gauge was 2-7/8" and you can make a good guess at most of the other dimensions from the photos.
Another option might be to ask the TCA museum people for help.
I'm not sure if they have an original or a repro on display there. If they do, I'm sure they would be happy to take some measurements for you.
...and I second the comment about Joe. I'm sure he will be willing to be of some help to you.
Jim