My 48 has the inner sheet metal where the tank would have been. The tank was mounted outside the frame.
In smaller trucks, same year, the tank was inside the frame.
I think 1949 is the year the tanks came back in the cab. On the other side of the coin is late 47 and most if not all of 48 the tanks should be outside of the cab.

Grigg


1951 GMC 250 in the Project Journals
1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
1952 Chevrolet 3800 pickup
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