Find cross pieces under metal roof to mount solar panel?

I recently saw someone post they had doubled up the panel "L" mounting brackets so they now looked like "T"'s (basically took two L's and put them back to back). This doubled the contact surface with the roof. They then used the 3M VBM tape to attach the panels to the roof. Then Dicor over top. No screws and had no issues.
Unconventional, but something to consider given you aren't adding more roof holes and you can mount it anywhere on the roof.