ok, here goes. Excuse the drawing, but this should illustrate just about what was done. 2 radiators were used, one underneath the floor, in the chassis, the second on the side of the engine bay (much smaller).
scan0006.jpg
The one underneath was quite a thick core, +- 100 mm. It was specially built for him, cross flow with a twist, as can be seen from the picture. The top tank was essentially split in 2. The bottom one had a scoop on it which can be seen in the side view below. From the side, you could hardly see it. (I have fond memories of sleeping on the floor above the radiator, nice and warm in the karoo at night

) The one in the engine bay had a fan fitted, with a normal electronic switch. This was a blank, i.e. no filler cap (also a cross flow). What my dad did was cut a hole in the wheel arch and build a scoop to direct airflow into the small radiator too. In the end, he also connected a switch on the dash to manually engage the fan when heading up mountain passes, but hardly ever used it. Pressure cap was built into a modified tank right at the tailgate for ease of use. Not the most scientific, but sure as hell did work. Let me know if you need any further info. Hope this helps!!
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