You could use nuts and washers, but this is just as simple.
1. Remove all strings
2. remove trem system from the body. Move the springs down to the lowest setting on the post (furthest from the plate)
3. Adjust tailpiece with an allen (hex) key to be as low as possible, but so that you can still get strings underneath. ALWAYS do this with strings removed or you will damage the plate.
4. Replace strings.
With the springs at full tension, and no sway coming from the vibrato, the brige is as good as locked.
