QUOTE(shep854 @ Mon 18 May 2009 1220)

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That's also where the LVT(H) came in. The WWII originals had 75mm how, later ones had 105mm how.
It could be argued that the original had 37mm, in a turret like that of the M3 Light, the next generation had a turret like that of the HMC M8 with the 75mm pack. There were attempted to put into service an LVT with a M24 turret. but was a bit top heavy.
Thr interesting part about these was that the LVT (A) - with the 75mm was considered to be underarmed, as it only had a .50cal for close in defence, in comaprison with the 37mm armed LVT (A)-1, which had two machine gun tubs in the rear hull as well as a MMG coax. Later LVT(A)-4 had two .30 in the turret rear as well as another MG in the hull front for the assistant driver to use.
The Squadrom book ahs two photos of LVT 4 carrying 105mm howitzers, one in the cargo hold, the other above the cargo hold. The one in the hold appears to have had its shield removed. This would indicate that even if it had to have its shield removed a 105mm howitzer would be able to be carried by a LCVP, manhandling it up a sandy beach would be something else again.