My 1942 Chevy accessories brochure shows several optional radios from the short wave unit, down to the 'Universal' car or truck radio. Ad states "This new radio will fit any car or truck regardless of year or model". This universal (five tube, four push button) radio is a long slender thing that fits under the dash in the trucks.
BTW, the last few pages shows just truck options for 42: beautiful grill guard, bumper guards, dual horns and the optional passenger side wiper unit. What a luxury!
NOTE- Check out the post "38 Radio on ebay". This is the 42-46 "Universal" unit that GM used for trucks and cars. The other radios mentioned with control head and cables running to the radio mounted on the firewall, could be also used in a truck. Although the truck dash did not have a radio opening as such and you'd have to mount the controls under dash.
