I have two tanks under the floor on my 79 G30 they are torpedo style tanks and sit between the outer chassis rail and the rocker panels. Fitting required a little cutting to the strengthening plates that sit in the gap.
Have a look on this thread for photos.....

https://www.vanning.com/threads/ubb...rolet-g20-lpg-conversion.html#Post744898

79 chevy G30 cobra camper conversion.
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