If the OP wants to take issue with harassment, they document it for a long enough sample-size of time to establish it is occurring. The covering of tattoos may be harassment BUT it's perfectly valid according to the uniform guidelines.
That in itself is just a hot-button issue and the OP fell for it, plain and simple. Many new people do.
I suggest filing Art. 37 but I wouldn't expect much change in the near-term. But as long as you continue to document everything, and do YOUR part (i.e. let management harass you over nothing, don't ever get visibly upset, only internally disappointed), it should eventually roll off and maybe you won't have a problem again.