A lot of the Pacific Shermans did have (105mm)Howitzers/Haubitze fitted.
A large number had Flammwerfer fitted instead of the main cannon, and a few had main cannon, plus Flammwerfer, plus mg, the least common variant actually being the 76mm Sherman.
The M3 Medium Tank (Grant/Lee) was employed in the pacific for far longer than in Europe because it's main gun was, like the 75mm Sherman weapon, very good at firing HE shells into bunkers.
Where in Europe Shermans were basically either 76mm, 75mm, or 105mm, with the occasional Firefly 17pdr thrown into the mix, in the Pacific the Shermans used were rather more different, as noted above.
In Europe enemy troops were in concrete bunkers, behind walls, or in other panzers. In the Pacific, enemy troops were in log bunkers, and caves.
Thus, in the Pacific Flame weapons and high explosive shells were (by comparison)used in greater numbers than in Europe.
Genial and Respectful Regards, Uyraell.