Is it the T34/88, used late war in the baltic states by the Germans? Proberly one only converted, a basic T34 hull with a classic 88 flak gun complete with shield stuck on the top. No idea what the flames of war rules are but i would thinks its like a Nashorn. Never seen a photo only a drawing, cant remember where!
I also saw a pak 40 with a wooden sheild around in a wargame mag.
In short the hulls where used a lot by the Germans, from turretless tractors, to mounting a quad 20mm flak etc..., so with the right opponent and a descent model why not do something unique?