I would like to get any information on a tortionbar front suspension swap from a 1978 Dodge Maginum to a 1938 plymouth business coupe.
Any info or instructions would be greatly appreciated.

Thanks,
Mopar

The first thing you need to know is what the front tread width(centerline of tire to centerline of tire) on the 38 is compared to the Magnum. If they Magnum is substantially wider, say more than 1 1/2 inches, look for a narrower unit, perhaps from a Duster/Swinger/Demon/Dart/Twister/Sport.
Also what is the wheelbase (center of front hub to center of rear hub) of the 38 compared to the Magnum. Too great a difference in this dimension may affect the turning radius and tire scrub of your front end.