Alright, made some good progress tonight. I routed a hole for the table stepper and gears with the little dremel. This was a bit of an exercise in patience as the dremel appears to be designed for smaller tasks, but it worked as long as I routed thin layers at a time.
The tensioner has been put together much like it was in the Scanner tray.
All in all this looks like it will work well. The only concern I had is the base, it being wood means its not in the slightest flat. Looking at that for a minute I realized I should glue 2 wooden 1x1" across the bottom to take out the warp. It's drying now, tomorrow we'll see if they hold.