I talked to HiTech about this at the Con a year ago or two. He said Pyro had a towed arty piece he was looking at adding, probably towed by one of the half-tracks. Nothing since then, though. It would be cool to model the German 88, as it could be used for AAA, traditional artillery, and as a direct-fire anti-tank weapon. Notice that a lot of V-bases have revetments, which would make an ideal place to set up the arty.