Thank you @Bob_Carpenter!
I guess I have scoured the forums and docs and wanted to have a google-able resource for posterity that is this different (?) case. Every complete case I can find in the forums/docs is, as you explained above, a function of a single parameter, used on the LHS. This post from @sakrejda above (that reponded to a year ago) is interesting because he included a Jacobian correction for a parameter used only on the RHS. If your last post applied to any parameter transform, even if used only on the RHS, then why didn’t we also need to add log(abs(theta2)) as well, to get the correct distribution on sigma2_unit from @sakrejda’s same code snippet?
Thank you again!