Need Help! National Guard Armored Cars 1920s & 30s and a bit of Outlaw History

It took me awhile to find my photograph that I obtained many years ago, but I finally found it today (see below).  So, I am now trying to find out more about it.  Does anyone knows what this is?

Click to enlarge

Here is what I can tell you, there is nothing written on the back of the photograph, except the number "13".  So that is no help.  As you can see written on the truck, it belongs to a Machine Gun Company of an unknown Regiment.  But it does have the abbreviation for Missouri after the word, Regiment.  With that little bit of information and the large spotlight mounted on it, I am very sure that it was an armored car for the 2nd Artillery Regiment (Anti-Aircraft) / 203rd Artillery Regiment, (Anti-Aircraft), Missouri Army National Guard.  Below is a rough history of the regiment taken from the 1934 book, History of the Missouri National Guard, by the Military Council, Missouri National Guard.

203rd Unit Crest (Left side - the right side would be facing the opposite direction)

The 2nd Artillery Regiment, (Anti-Aircraft) was started in July 1920, but not complete until July 1921.  It was re-designated to the 203rd Artillery Regiment, (Anti-Aircraft) in April 1924.  Then later it was renamed again to the 203rd Coastal Artillery Regiment (Anti-Aircraft) before 1934.

Now here is the crux that I can't figure out.  It clearly states in the photo that it belongs to a Machine Gun Company, but all of the units in an artillery regiment are called "Batteries".  I can't find any reference to a Machine Gun Company.  Now there are two possible answer to this.  First is that several of the Batteries that made up the 2nd Artillery, carried the lineage of Machine Gun Companies from the 128th, 129th, and the 130th Machine Gun Battalions.  Or, secondly, and I think this is the right answer, that there was a separate Machine Gun Company created on July 7, 1920, under Captain James A. Frow in Nevada, Missouri.  It was this company that was to become the nucleus for the whole artillery regiment.  I also believe that this might explain why the markings on the vehicle does not say Machine Gun Battalion on it, which could support that this truck might be for one of the batteries that came from the 128th, 129th, or 130th MG Battalions.

The six police officers killed at the Young Brothers Massacre

Another interesting thing about this unit was on January 2, 1932, Battery F of the 203rd was called out to support the local law enforcement officials in Greene County & Springfield, Missouri, after the largest lost of life of law enforcement officers in a single shoot out to date, normally referred to as the "Young Brothers' Massacre" (only the 9-11, 2001, terror attack and the Milwaukee bombing in 1917, killed more police officers in a single event in the USA.)  The events of the Young Brothers Massacre are very sad indeed, leaving the Greene County sheriff and five Springfield police officers dead of the eleven men that went to arrest the two brothers.  Both the brothers escape before the return of more police men and the National Guard who had orders to use their machine guns on the house if necessary.  More can be read on the massacre at the Wiki site here or with this book, The Young Brothers Massacre, by Paul & Mary Barrett (which I have read) or another book, "We're Dead, Come On In", by Bruce Davis (I have not read this one yet).  An additional note; "F" Battery would get the rating of "Excellence" during their 1932 annual training at Fort Still, for their machine gun scores by Federal inspectors.  Had the Young Brothers waited to fight it out, I think the National Guardsmen would had made short work of them.

After reading a bit more on the Young Brothers Massacre again, it got me thinking about the Indiana National Guard that was used to guard the Crown Point Jail in 1934 where John Dillinger escape with the use of a wooden gun.  In some reports I have seen, it states that the National Guard had armored cars there.  So I would also like to know what unit was there and what kind of armored cars that they had at the time.

The National Guard scene from the 2009 movie, Public Enemies

 Any help will be very helpful,

Sapper