I've got a '71 Cutlass Supreme which came with a '67 425 stuffed into the fenders. Its a D block with C heads, but my big concern is lifter angle and diameter. I've read the information available but I am still confused. I know the Toro's had a 39 degree with .921 diameter lifters and most of the normal blocks had the older 45 degree with .842 lifters. Now I've read that the '67 blocks were all standardized and had 39 degrees with .842 lifters. Anyone follow where I'm going with this? I need to select a bump stick soon and need to know what I'm working with.