You could, but why would you want to? AFAIK, the Archer was the only tracked SPG to do so. Although, there were some wheeled SPGs that did so. http://vignette3.wikia.nocookie.net/world-war-2/images/5/50/Portee2PDR.jpg]/img] [QUOTE="knightdepaix, post: 806288, member: 30666"]2) could a backward driven Italian tank chasis mount a larger caliber and heavier gun ? An Italian Nashhorn ...[/QUOTE] It has nothing to do with which way the gun is facing, but how much weight the tank chassis and suspension can effectively support. If the chassis and suspension cannot support the additional weight...It matters not if the gun is facing fore or aft. [QUOTE="knightdepaix, post: 806288, member: 30666"]3) If possible, how about an enclosed in casemate? An Italian Jagdpanther...[/QUOTE] The Italians did not have a tank chassis capable of taking the weight. They might have developed a Stug IV knockoff, based on the P 26/40 chassis, but production would have been very low, if any, before the Italians surrendered in 1943.