>>380
M777をトラックに載せれば良いだけの話だろうに。

https://www.navalnews.com/wp-content/uploads/2020/11/AM-General%E2%80%99s-155mm-6x6-%E2%80%9CBrutus%E2%80%9D-1024x672.jpg
https://www.google.com/amp/s/breakingdefense.com/2021/05/army-tries-out-humvee-mounted-howitzer/amp/

The Army’s currently conducting an informal “shoot off” of four alternative wheeled howitzers;
the reported contenders are
American (AM General’s Brutus),
Israeli (Elbit’s Iron Saber),
Swedish (BAE’s Archer), and even
Serbian (Yugoimport’s NORA).