Can we plot only one element of a vector or array-valued variable in a trace?

I have a model that is “localized” for robustness a la A General Model for Robust Bayesian Modeling so that I have separate variance parameters for each data point.
I would like to explore this model to diagnose divergences, but I cannot practically plot the full vector of these variables – there are more than a thousand!
Is there some way to plot only selected members of a vector (or array) valued variable in a trace?