I found it a little annoying whenever I wanted to swap the motor mount off my Zen Toolworks CNC mill, the washers and nuts would be difficult to work with and regularly fall into the machine. I already super glued most of the washers to the mill, but to improve swapping accessories, I cut these little jigs out of 4mm acrylic to hold the bolts from turning. The photo below shows the jigs with the nuts not inserted yet. Once the mill is reassembled, I only need to deal with the accessory I am attaching, and the four bolts used to hold it down. Much easier!