Monty, here's some (semi) convergent evolution based upon the same requirement -- massive firepower in a compact armored package.
US T31 (or is it T34) Demolition Tank = 105mm Howitzer, plus two rocket launchers on either side, capable of being reloaded from under armor.
German Pz IV project to use 7.5cm Recoilless Rifles. Attached is an icon that got done uh, ten years ago for the RGW Mod for SPWW2v2 DOS. Maybe you can use it for inspiration.
Re: WinSP MBT: Das Reich
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