A 2 is not an upside
down 5
I've never been good with clocks with hands, being dyslexic and all. I wanted a big clock that I could see from across the shop where I work, Barber's Shop Automotive in Sacramento.
It had to fit between the Berlina clip and the yellow pegboard, so I designed six inch high displays. I cut down an aluminum movie poster frame that I got from a thrift store. And drilled many holes in the particle board, transfered from a piece of paper by a center punch. You know, to give it a consistently homemade look.
This thing runs off of a pre-programmed clock chip putting out binary coded decimal (BCD) , and four BCD to nixie chips (10 number), from http://www.allspectrum.com/store/product_info.php?products_id=352 and...
For the real novel part, a special "number state" to 12 segment adapters, made from a matrix of adhesive copper trace and diodes. Those are dumpster-dived clear plastic picture-frame inserts, I get extra style points for that.
Yes, I know I did it the hard way. I didn't have time to learn to program microcontrollers then.