1955;

Have you tried the 4BTSwaps.com site? They have a forum dedicated to 6BT/5.9 Cummins conversions. Those folks have been there, done that. I think there are some Stovebolt members there too. Good luck

http://www.4btswaps.com/forum/forumdisplay.php?14-Cummins-6BT-5.9-Conversions

SimS