mini truck chassis

The key here is the word 'develop'.

This implies a process of evolution, so make an educated guess based on what criteria you consider important. E.G Cost, strength, local supply? whatever...build it ...test it to destruction and repeat as often as is necessary.

Or feed a load of info into a coputer analyse it until it seems right, then repeat the build & test stage, because the computer won't do it all anyhow.

Del