Making sure your steel bellhousing is in alignment is a key step in making sure your transmission will live a long happy life. Misalignment of the input shaft with the crank can lead to premature bearing failure on these T56 magnum transmissions. The spec is .005 (5 thousands) so follow the video below to make sure your bell is where it should be.
You can use the bellhousing index plate I sell which has a large diameter opening for easy indicating.
If you need offset dowels, they can be found direct from Holley's website, or on Summit Racing or Jegs. Here are the quicktime part numbers:
RM-145
RM-146
RM-147