All of our car trailer plans include detailed engineering drawings of the chassis frame, ramp and deck which include specific weld specifications. We don't include too much detail around specific trailer parts such as brakes, wheel setups, hitch etc. These items are available from many different suppliers around the world so we try and keep them as generic as possible.
Unfortunately we don't have any designs for a fifth wheel trailer, as these are not as common in Australia as they are in the US. We do want you to know that we only sell ADR compliant trailer plans.