Easiest way to solve this is to use the Cloyes billet cover with the adjustable cam button. About $125. Looks great, doesn't flex and allows fine adjustment of Cam button lash to prevent walking.
I use it and it works well. Set it to zero lash cold and when things warm up it's set. It has an adjustable roller button built in. Here's what it looks like before installing. As a side benefit it allows cam changes with out pulling the balancer or pan.