While searching on the internet for material which would be appropriate for the 92nd AFA Bn web page I came across several web sites that are involved in modeling military weapons and vehicles. I noticed that in order to make authentic models the builders used original specifications sometimes. I contacted one modeler in Holland, who it turns out has 235 different sets of specifications, including the M-41 155 Howitzer SP. When I told him why I was interested in the M-41 he graciously offered to make copies and send them to me at no cost. I have loaded the ones I thought would be of interest and also readable on the web page.
History of the Development of the M-41 155mm SP Motor Gun Carriage
           ( Excerpted from MMIR Magazine Summer 1997 by Nick Vaston )

"The M-41 can trace it's roots back to the summer of 1941 when the U.S. Army Ordinance Committee requested a light-weight, self propelled gun. Two prototypes based on a stretched M-5 Stuart hull were built by Cadillac Company, The T-1 mounting a 4.5 inch gun;  and the T-64 mounting a 155mm Howitzer M1. In February of 1943 both vehicles were sent to the field artillery board at Ft. Bragg for evaluation.The vehicles performed satisfactorily but had problems in that the gun was unable to depress below horizontal and the manually operated spade required reinforcing. In addition, when firing the main gun, damage was incurred by the stowage on the front of the vehicle and there was a lack of adequate ventilation to the driver's compartment.

During this time a similar vehicle was being developed  following the combat team concept. This was a series of special purpose vehicles and self propelled guns based on the T-24 or Chaffee chassis. The armored board rejected the 4.5 inch gun in favor of the 155mm Howitzer. In January 1944 construction of a pilot vehicle designated T-64E1 was approved. Acontract was issued to Cadillac in January 1945 and a pilot vehicle was delivered to Fort Knox for evaluation. The vehicle was superior to the T-16 or the T-64 automotively and included improved suspension of the M-24. Minor modifications were made and the vehicle was accepted for service as the 155mm Howitzer motor gun carriage M-41

The M-41 used basically the same chassis as the M-19 anti-aircraft motor carriage with the engine mounted in the center of the vehicle, and the drivers compartment being almost identical to the M-24. The 155mm Howitzer was mounted to the rear allowing 45 degree elevation and  5 degree depression of the weapon, with 205 degree traverse to the right and 17 degree to the left. A maximum of 22 155mm rounds could be stored under the gun. Due to the lack of storage and crew space, a companion vehicle was proposed as a munitions carrier, but this was canceled due to the end of the war (WWII). Extra rounds were usually carried in a towed M-39 cargo trailer.

Production was limited to only 85  vehicles manufactured by the Massy Harris Co., with one being shipped to Britain for evaluation. The M-41 saw service in the post war years, as well as extensive action in the Korean War, most notably with the 92nd Armored Field Artillery Bn. (Red Devils), where it set several firing records. The mobility and fire power of the M-41 allowed it to be utilized in a multitude of different roles, where it was employed with devastating effects. It remained in service until the mid 1950's, when it was finally retired from service."