The main problem with the Haynes Book Of Fiction was that they took a brand new car, and took the engine out and dismantled it on the bench.
"To remove the exhaust manifold, simply undo the 8 nuts holding it in place"
No Shit, Sherlock.
Only, with a real car, you need to break your arm in 3 places just to *touch* the nuts in question, never mind getting a spanner on them.
And then, if the car has actually been driven, the nuts are seized to the point that they will shear the studs before coming off.