I do most of my painting without any hardware attached, so I use a slight variation of the x-acto knife holder. Instead of keeping the blade in the knife, I replaced it with the shaft of a long skinny nail. I then press the nail into the rear of the bait where my screw will eventually go. The compression of the nail will hold on to your wood while you do all your painting, and you can hold the handle of the knife in a vise or roll it behind a netting filter to add scales, etc.
When it's ready to dry, simply release the nail from the x-acto knife, and stick it into your drying wheel foam for turning/drying. Here's a quick image of my holder.
Hope that helps (although I have to say...I might switch to that RCA jack appraoch...it looks really good!!!)
What is that circle in the background? It's a knitting hoop with cloth mesh stuck in it that I use for painting fish scales. I press/roll the bait along the back of the netting, while spraying through the front...and it creates a great scale effect. You can pick up those knitting hoops for $1 at most craft stores and it's an easy way to add scales to baits. :-)