Wow. It is great to fall in with the likes of Nigel, Dan, Grant, Jesse, Ken, Alan, DJ, Roy, and yourself, Dave.
I fell in love with those canon half-tracks in Italy the moment I saw one rounding a cliff-road when the TV movie: "The Execution of Private Slovak," was shown, as a child. This was a 105mm, and it appeared again in "Kelly's Heroes." Back then, I never knew anything different, with regard to the Rangers. As a thirteen-year old, I got 'SACREDLY CONFIRMED' a modeler upon seeing the grown man, J Carson [whom has recently re-appeared at our modeling club, "CSM," after decades and decades of absence], build this sort of weapon as a conversion, in our local model club. During the mid-70's, Mom dropped me off there downtown, and picked me up at the Frische's restaurant some blocks away, later that night…each month…way back then.
My Uncle served in the 1st Armored Division, and in later years I learned how C Co. of the 81st Rcn. Bn. went through Africa, and on to Pisa, with those little T-30 Pack howitzers mounted in the half-tracks. One actually shot a pillar out of the leaning tower, as Jerry had observers up there.
I heard how everyone got out of the half-track and sat on the front bumper when advancing up a mountain curve, as the front tires would have otherwise lifted so far off the ground that the vehicle would not turn.
Back to the subject of this build: American Tank Destroyer units had the T-12 three-inch half-track canon in Africa, as did some of the English units, months later, around Cassino. I think the canon was of French design--but as to this Ranger version: 'Time Life' has published a late 1970's series of hard-back volumes on WWII. The one about "The Italian campaign" has a re-print of the Magazine photos. This book could be had for under ten dollars at any good used book store.
In reading about the Rangers, I am very impressed by the Winter Line. The Rangers were lined up in the mud on the back side of the mountain range lobbing those half-track projectiles over the ridge--I think the area was called Fontana--while the 1st Special Service Force to the west went climbing an insanely unapproachable angle to over-run Mount La Difensa, the high point of that line. A movie producer named Huston made a movie about the 353rd Tank Battalion moving forward into San Pietro, with the Texas T-Patchers' after that break in the Winter line. Further study will find that my Uncle's 6th Armored Infantry, 1st Armored Division, with the 760th Tank Battalion, was in on the assault of the hill just west of San Pietro called Mt. Porchia. Mt. Porchia was defended by the Herman Goering Division. Some Allied Italian troops were instrumental at this point as well.
The Rangers were hit hard at Anzio, and I believe a whole Company was captured. The 1st Special Service force came in and took up the line along the canal to the east and south of Cisterna. Audie Murphy's 3rd Infantry Division was alongside to the north, towards Cisterna. An evocative photo of a 1st Special Force T12 half-track appears on page 217 of the 1947 book by Lt. Col. Robert D. Burhans: "The First Special Service Force: A War History of The North Americans: 1942-1944." This book is re-printed in 1996 by The Battery Press, Inc. P.O. Box 198885; Nashville, Tennessee, 37219. The Battery Press is a premiere publisher of unit history re-prints. Everyone should become familiar with their product line.
Those pictures in the Michel de Trez book appear on pp. 474-475.
Dave, I read all this stuff back in the 1990's, and have commented here by line of memory. I dimly re-call other images of this subject, and will hopefully find more particular reference in the weeks ahead, as your build proceeds.
Incidentally, these T-12 half-tracks were used in 1942 as coastal artillery there on Guadalcanal for several weeks up until the 3rd Marine Defense Battalion got set up and established…I mean, the U.S.N. pulled out before the defense weapons were unloaded.
http://www.youtube.com/watch?v=BIgbZIksHWs 
