I received a commission request for 3 BIG Battlewagon sized Gobsmashas for a Russian Horde themed Ork army. After poking around online I settled on the SU122 and SU152 as inspiration:
The overall look will be influenced by the Red Metal, but they won't be copies. Here's the beginning of the first:
Quite a lot of work left to do, but I like the profile. I'll build each body in turn so I can work each of the builds at the same time. I'll get a more uniform look to them if I do all the detailing together.