You will have to sift all the information, make judgements on who to believe and what seems right for you, then, get on with it.
Some people collect vast amounts of data, only to become paralysed by indecision. Sometimes it is better not to know everything!
Be very honest with yourself. Do not be afraid to go back to the drawing board if data comes to hand. Try to make changes at the planning stage, and not when you are deep into the project.
Only now should you consider buying the vehicle and major components,
Order the larger parts as soon as you have finalised your decisions (and have the money), as some parts will need to come from overseas, and will take some time.
This will give you some time to look at other factors, and read up on how to do it. Now is the time to be talking to your local Department of Transport and “tame” Engineer. Do it early.
This paper is by no means definitive, and is the best I could do at the time. I relied heavily on the net and my own experience. There will be people with far more knowledge than myself, and I welcome any additions or alterations to the text. Edward Booth