Seriously? Everyone who's built their chassis from scratch per the book marked out their build table from this drawing, and certainly in my case the tubes fell into their places like pieces of the puzzle.
I did a quick check with the calculator, and it seems that the 1118 diagonal is an error, it should be 1148.6. Other numbers look OK, 1313 is in fact 1312.5, and 808 is 807.7.
The length of BR1/BR2 is 993.27 based on this plan (993 in the appendix) , and BR3/BR4 should be 584.34 (584 in the appendix).
So basically other than the 1118 diagonal all other measurements are true, rounded to a millimetre.