that is 2 guys for 7 hours. One decent wrench who has never done one before can do it in 7 hrs if he can borrow some experienced hands/advise a couple of times during the process. So 7 for him and 1 for the master. A total of 8.
Not sure what the book allows for the job, but if it is 14 hrs you need to find a good independant to do the work.