with a 3.55 rear an OD isn't much use unless the majority of your driving will be on flat highways .... and the Saginaw has a 7 bolt side cover, you have 66 or earlier Muncies, so no you don't have to switch the covers
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics
