4 sp auto into 1ts gen d-50

Has anyone done or thought about swapping a 4 spd OD auto into a 1st gen D50 with a 2.6 3 spd auto? It should bolt right up; maybe a driveshaft shortening on the front shaft?
A site for Mitsubishi Mighty Max and Dodge Ram 50 Enthusiasts.
http://www.mightyram50.net/phpBB3/