Yes the sanding and finishing seem to take so much of our time on a project but it is so vitally important to the end result.
I have been taking stock of the time I have in the shop recently and figuring out how much time it takes to complete an item. A Butcher Block can take me up to 7 hours of "hands on" dedicated time to complete and this of course does not include every aspect of the process. It has been interesting well, to me anyway, figuring out how to best utilize and prioritize my time in the shop. If I were building your design of clock, I would have to give myself at least 40 hrs out of the gate so it's not too far off your estimated time. Time well spent in my books.
I have been trying to find the time to build another Curio Cabinet but I'm tied up with Butcher Blocks, Bandsaw Boxes,shop upgrades(that has been a biggie lately) and inlay components. I'll figure it out eventually.

Take care Glen.
Derek