How long to machine engine?
It took about 2 months start to finish in the machine shop for my engine. Most of that time was delays on my part, ordering parts and finding time to get them to the shop.
Worest thing you can do is not put any kind of time goal on the shop. If you say take your time, then they will always (and rightfully so) move you to the back of the line for some one that wants it quicker because you have given them permission.