Can anyone tell me the correct length of the driveshaft for a 1974 Duster, smallblock with 727 in standard locations with an 8 3/4 489 case? The rear is on stock springs in factory location. I'm trying to get my lil hot rod put together for when I get back from Iraq. Should be stateside in about 6 weeks, and don't want to have too many things to do before driving it. Thanks!!