Welcome Aboard Haywire,
I believe the picture in question shows one of the many Chevy variants with the bullnosed hood design, sort of reminiscent of the thirties and forties styles. The LRDG Truck from Tamiya would give you a good starting point. The 2 pounder would have to be from a smaller maker, I know there are one or two out there somewhere. I used a scratchbuilt gun when I did the one I made a few years back, I got my info on the gun from an old British Periodical from the fifties, the picture you saw was probably in the Infantry Guns Book that was a paperback from the same company only a later publication.
Anyway you get to do some scratch building to come up with a shortie stake body without the stakes, sheet plastic in .060 was the material I used to create the steel framing that made up the bed framework. I know that all the rest of the construction was wood, I used to own a stakebody 1940 Chevy one ton, just like the one depicted in the kit. You can sub in Balsa, easiest, or basswood, harder but more durable and easier to finiish. Stretched sprue or if you want to get fancy a couple of different sized small plastic rod will furnish you all the hold downs and long shanked rivets that held the wood down to the frame, trapping the metal framework in between the 4X8's that made up the runners mounted to the frame and the 2X6's boards that made up the floor of the bed. The gun was mounted on to big blocks of wood and strapped down to the bed with metal strapping and sandbagged for extra security. The big blocks of wood were spiked to the 2X6 bed boards. The only thing that they did to modify the gun in any way that I could see was that they took the wheels and tires off. they used chain over the gun trails to help hold it down on the bed and frame of the truck. Pretty much a field expedient that they used to get the immediate job done, they needed SPG type weaponery to chase the Italians across the frontier before Rommel arrived and played see saw with them for a while. I've also seen pictures of the British Quad with a six pounder in the Portee mount as they called it. I believe the Quad in question was a Canadian Fat Four type with a wooden flat bed, the Italeri one is a good representation to start with.
That's about all I know about the Portee 2 pounders that the British used in North Africa, you might check out 'Desert Rats At War' by George Forty, and 'The Guns, 1939-1945', a Ballentines Illustrated History of WW II, Weapons Book #11, and Time Life's WW II Series volume "The War In The Desert" for more info. I have found lot's of the old Ballentine's Illuastrated History of WW II in local second hand book stores here iun Las Vegas, most public Libraries will have a copy of the Time Life series or two laying about.. You might also check out the different site links that we have I know The Bovington Collections are reporesented there and surely they have a picture or two of a 2 pounder Good luck on an interesting and fun conversion project that us old timers like to call "kit Bashing" for obvious reasons.
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