If you attach the physics settings to the dome instead of the base, the end result is that upon getting hit the base will stay anchored to the earth but the turret & barrels will fly off into the sunset, leaving you with a visually destroyed mortar.
About that mortair - set it’s parent class to tank and then u easily can make them behave in similar fashion as other tanks about taking dmg. And basically just disable them when you hit them enough. Ofc you miss out on all of the fun you get by knocking them miles away.