In reality... Hour wise for what you described could range from 150-300 depending on how far apart the interior is going and what "little" things are being done during the restoration. Is the engine and drivetrain still installed? was this a shell on rollers? are they duplicating somewhat factory procedures? do they need to detail the rear end? replace brake and fuel lines?

40 hrs week x 4 weeks is 160 hours -
A general shop may only work on the car 20-30% of that time during the month depending on other workload which is why restorations take so long.

Generally paint work is estimated seperatly from disassembly and assembly work on this type of stuff. Paint work could range from $6,000- $20,000 depending on the shop. Most shops charge hourly for mechanical work and depending on the area that could range from $60.00-$150/hr