Not all gassers sat up high in the front,so you vision could still be authentic. Although,trucks would have more traction/weight transfer issues than cars being so much lighter in the rear.
I saw a SWB Stepside for sale somewhere recently with no engine/trans.I considered it but felt they wanted too much considering it had a '73+ bed and was really just the front suspension mod on a who knows what primered body.
There are a couple photoshopped in this thread:
http://67-72chevytrucks.com/vboard/s...d.php?t=304189