@Googlydoogly.
Exactly. Those mounts were for a jib crane attachment,so engines and such could be self extracted. I am thinking a good material for the mantlet cover could be a fine weave cloth. Cnavas does look " coarse,so at 1/16th it would fill the bill. The only downside it would be stiffer,as the cloth is 1:1,and the scale of the tank is smaller.
I also added some tie down loops on the top of the rack,on the side of the turret.