The newest volume of Nuts & Bolts will be dealing with Horch's leichte Panzerspähwagen on Einheitsfahrgestell I & II for s.Pkw. Sd.Kfz. 221, 222, 223, 247, 260, 261 and variants
This is partial text from the full article (usually with photos) at https://armorama.com/news/nuts-bolts-vol-47-sd-kfz--221-and-variants