Just to follow up on Poncho's response, here are some links to my journals.
I have '78 twin I-beams under my '32 pickup mounted with air bags as shown in this photo. You can see more of this chassis here.
The second photo show how these axles look in the finished truck.
I built my '31 roadster using '81 twin beam and coil overs as shown in this photo. You can see more of the roadster chassis and suspension construction starting here.
The second photo shows how these axles look in the finished car.
My '29 Sedan Delivery has '79 twin beams with quarter elliptical leaf springs as shown in the first photo below. You can see this entire chassis and suspension fabrication starting here.
The last two photos show how these axles look in the finished car.