here is a second factory photo shot from Service Publications disc of factory photos showing the GT from the front. While this does not show the floor pan it does show no windscreen.
I would say the the chassis and running gear was 'As Per' a full truck with the only body parts being a flat faced cowl with doghouse and dash plus the floor pan. You could rig a bracket to support a seat where the floor cut out is
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Cheers
Cliff Hutchings
aka MrRoo S.I.R.
"and on the 8th day he made trucks so that man, made on the 7th day, had shelter when woman threw him out for the night"
MrRoo says "TRUCKS ROOLE"
