155s weren't used till modern wars like desert storm i think and also I'm pretty sure there was already a post about this, I think it was mine.....
Inaccurate. The M12 GMC was a self-propelled 155mm artillery piece fielded by the U.S. Army in WWII. the gun was a m1917 or m1918, both derived from the French 155mm GPF of WWI mounted on an M3 (Grant/Lee) hull with M4 suspension. There was also the towed 155mm M1/M2 gun, the famed "Long Tom". Later the m1/m2 was mounted on a M4 chassis & designated the M40 GMC, aka "King Kong" and saw service beginning in Korea, except for one single M40 that made it to Europe before the end of WWII.
But anyhow, IMHO, artillery would not be a good idea for AH at this juncture.