I am not going to argue the title as it does correct the detail in the end of the title. I thought it may be due to a truck set up with MG’s for anti aircraft work being changed to one with tha Katyusha rocket launchers
Yup - it’s the HB short-wheelbase CCKW (GMC 2-1/2 ton truck) with the bed replaced with the launchers. IIRC this is an accurate lash-up, unlike the Italeri one based on a post-war Soviet copy of the CCKW.
But of course it ain’t a GAZ-AAA, which was a three-axle modification of Russian-built Ford model A trucks…
The postwar BM-13-16 were built on the ZiS (renamed ZiL when Staling had croaked) 151 chassis. The only thing incorrect with Italeris old kit would be any claims that it is/was a wartime Katyusha.