For whats its worth, I had built my car having no book or access to one, using only bits of info and plans available on the net.
The best part of having gone this way was the fact that I could used the best bits here and there and inter-marry it all in one chassis having the best of all worlds....
The chassis is a McSorley 442E, modified by incorporating additional stiffening after reading a detailed stress analysis of the book chassis and the recommendations. The rear IRS is loosely based on Rorty design but fine tuned / stiffened for Sierra
(and 185kw 3SGTE motor used) bits and the suspension all round my own design to the parameters I set out. Again my tutor being the goldmine of information available on the web - the secret however is to find the useful stuff as there are also a lot of misinformation out there.
My car nearly completed and still I need to see the inside of a seven type design/build book
Good luck with your build.