First off I have no plans for this Simulator. I am just building it as I go. I have made drawlings of it from time to time and but never keep them. My thinking is make the base 4 foot wide and that would be just right, not to wide not to small. I might end up about 9 or 10 foot long not sure yet. I have 2 cars I am looking at for my reference. One is a Revell Model the other is a die cast. The Firewall on the Revell is kind of desk shaped as is mine.