Warlord Games knows lugging guns around can be a pain, so they’ve got one that moves itself with the release of their Type 4 Ho-Ro gun platform.
From the website:
Add some heavy support to your Japanese forces with the Type 4 Ho-Ro self-propelled gun.
The gun crew was protected by an open gun shield with 25mm frontal armour, but was unprotected to the sides and rear, which made the vehicle vulnerable to close combat. Other issues with the design were that the gun had a traverse movement of only 3 degrees, and had a slow rate of fire due to its breech loader.