Please Disregard the non traditional car used for display. I've used this on a couple of cars with just different adapters made.I can no longer lay on the floor and weld and grind and paint so it was required e****ent for me. I could give exact dimensions but I think there is a lot of leeway there and it will work ok with out strict guidelines. I had some 1 1/2 x 14 gauge tubing that I had been given ,to thin for rollbar but sturdy enough for this .I made one for a friend with 2 inch square and it worked great too. The height will depend on your garage,the width will be determined by how high off the ground you want the car to be on it's side. Most cars are balanced at about the camshaft location but that is with a motor and trans. I like this because it's easy to store ,it's clear out of the way,(most rollovers have a piece that runs under the car and is always in the way.) I run a diagonal brace from the rollerover fixture to a point on the car with a existing hole to keep it all from racking. Thanks for looking.
A guy down the road has two big wagon wheel looking things - currently an El Camino is suspended between them. The look like the end off a big wire spool, must be 7-8' in diameter.