DIY German Conversions
The prolific Mr Richard Humble has released two stl conversion kits to allow players to produce two relatively obscure German armoured vehicles. The first kit is for the 10.5 cm K gepanzerte Selbstfahrlafette (Dicker Max) which was a prototype mounting a 105mm naval flak gun on a Panzer IV hull as a bunker buster. One of the prototypes burned during trials but the other one was used from January 1941 to the end of 1942 on the Eastern front. The stls allow you to convert a Rubicon Panzer IV Ausf D/E kit, although you will need to cut the hull as per the instructions on Richard's page.
The second kit is for a Sturmgeschütz (StuG) IV. As Krupp didn’t build the Panzer III used for StuG III they adapted the StuG superstructure to fit the Panzer IV. this kit allows you to convert the Rubicon Panzer IV Ausf J kit, although, again, you will need to cut the hull as per the instructions on Richard's page.