Coaster Cars

This morning I have begun thinking about the design of the coaster cars.  My overall vision is to produce a lifelike replica using aluminum for the frame and general structure outline.  Roller bearings will be used for the wheels.  Again aluminum will be used for the chassis.

I plan to use SolidWorks to model the cars in 3D before starting construction.  Without plans how will I know how to build them?  I've ridden plenty of coasters to understand the working mechanics of a wooden coaster car, but scaling the pieces without physically measuring each piece is going to be a challenge.  The best solution to this problem is to collect as many photos of actual coaster cars as possible.  Ideally I need a shot of a wooden car from the side, elevation view.  I've found some perfect photos randomly online, Bingo!

I will assume the gutter depth in the above photo is 5 1/2".  From this assumption I can scale relatively the dimensions of everything else to real-life measurements.

From these photos I will be able to scale off relative dimensions of the coaster car to reasonable accuracy. I'm sure my creative mind will add a bit of design beauty and originality to my model car.