Engine removal takes over 6 hours. By the time you remove the hood, rad, fuel lines, hoses, manifolds, exhaust system, shifter linkage, drive shaft and many other electrical conections the time adds up.
You can add another day just to remove all the small parts that need to be plated and cleaning of all the aluminium pieces. The plating doesn't cost too much but it's best to deliver nice clean rust free parts. If they're rusty you can sand blast them clean - more time for that. Figure on several hundered dollars to get the engine bay painted and then you can detail everything with black paint.
While you're at it you might as well detail the brake booster, rad, power steering pump, coat the manifolds and clean up all the wiring in the engine bay. This is how we do the cars that come through my shop. Engine rebuild with engine bay detailing is running in the mid teens right now.