Of the FC radars associated with S-60, SON-4 and SON-9 are towed equipments copied from US lend-lease kit, and seem to look pretty smilar, but SON-50 is vehicle mounted.
SON-4, “Whiff”, SCR-584 copy. “Dish is placed on the back of the roof. Wheel arches running the full width of the caravan near the rear of the caravan”.
SON-9, “Fire Can”. “Different dishes: 5,7,10 spokes & solid. Dish is placed on the front of the roof. Cut-out type wheel arches right at the rear of the caravan.”
SON-50 (RPK-1), “Flap Wheel”, picture shows a solid dish radar on top of a truck body on what looks like an Ural-375 chassis. Googling RPK-1 gets several piccies.
https://www.militaryfactory.com/armor/detail.asp?armor_id=163 says the towing vehicle for S-60 and associated FC equipment was Ural-375.
All the best,