Go to
http://ahecwebdds.carlisle.army.mil/...g=result&smd=2
or Google the US Army archive site and browse their manuals by WW2.
The
37mm gun, tank, M6 (mounted in tanks) FM 23-81 will have everything that you require.
The manuals are pdf and this one is 5.90Mb.
They also have many other manuals, including the Staghound.
Did I mention that they are free....?