I've mentioned S&S Models before. They make really affordable models in 15mm, 20mm and 28mm. They also make conversion kits and this is one of those. They do the fighting compartment, and gun, from a M17 to go on the back of The Plastic Soldier Company's M5 halftrack. It is easy and straight forward to build and I think painted up very well. I did a head swap on all the figures, adding some from PSC's Summer Soviet Infantry set.