In the above image from Histories & Lore: Robert's Rebellion, we see six Targaryen kings. I would like to determine which king is which before adding images of individual kings to articles. Based on their similarities to portraits by Amoka on the Wiki of Ice and Fire (which are based on descriptions provided by George R.R. Martin himself) I'm pretty sure the first is Aegon I Targaryen, the fifth is Maekar Targaryen and the sixth is Aegon V Targaryen. I'm not sure if the fourth is Baelor Targaryen or Aerys I Targaryen, and I have no idea who the second and third ones are.
Any input would be appreciated.