Most guys can't work on their cars 8 hrs. a day. If your retired who cares how long it takes. What else you gots ta do? Seriously, I would speculate it would take a seasoned 914 guy 40 hrs. to pull a car down to the shell. This is taking into consideration you have all your bins ready, your markers, various size freezer bags and good work bench space. You also need to understand that many of the parts you pull off the car will not be "good enough" when you start to try to put humpdy dumpdy back together again.
So while your car is at the shop you will spend another 10 hrs. Going through the bins by section, laying everything out on work benches in order from front to back or visa versa to assemble your punch list and get a large parts order ready for our member vendors. You have to do something with that pension money.
Now, if you can leave everything laid out in order until your car returns from the painter, Great! That will save time. If not you will need to repeat the second step and start over.
Then there is the parts cleaning process. Getting all the grit, grime and grease off everything you pulled from the car. Cleaning nuts and bolts, wiring harnesses, repairing terminal ends, putting together another large order for those special terminal boots and that stainless strap that goes on the brake reservoir because now you can't live with that rusty strap. This can take several days.
Once those parts are cleaned you can't just leave them raw. Out comes the masking tape and the bomb cans...
Ooops, blew another several hours.
Assembly is always harder because you first you have to be careful not to scratch it.
Then just when you think you were a smart guy and ordered all the parts you need you discover something that is now not fit to use. (dirk wrights disease) So you start over looking at your pile of parts, then the classified all over the internet, then eventually our member vendors again. Another big (but smaller this time) order is placed. Oh and don't forget the 20+ trips to the hardware store to replace the rusted and dirty nuts and bolts you "were" going to reuse....
We haven't even begun to explore the dirty engine, transaxle, trailing arms or front suspension stuff. This stuff can eat time. I would give yourself a month to go through the assembly. You'll end up finding yourself doing stuff like standing at the wire wheel cleaning bolts, then deciding it's not worth your time and heading to the store yet again to get another handful of fasteners....
Enjoy the process and you will do it again.