I bought the dowels from woodcraft
first i layer out where each dowel would go i then took it to the drill press set my depth to 1/4 inch.
I precut all the dowels on the bandsaw. and then started glueing. after glue was dry i sander it in my jet 22- 44 open end drum sander . As for time about 12 hours off and on.
So the dowels were the last thing you did? The board was complete when you were drilling the holes? I was wondering if you found some way to drill multiple blocks at the same time, but it sounds like every hole was one at a time and then not all the way through the block. Sounds time consuming, but I want to try this one of these days.