Unfortunately, the bell housing MUST be dialed in or you will experience a terrible problem with transmission shifting and you will eventually loose the front bearing on the input shaft of the tranny.
I just dialed my own bell housing in (Lakewood) and it was out 0.018" on the dial indicator. I was only able to get the bell housing within 0.005"...because the bell housing hole was 0.005" out of ROUND!
We actually dial them in a little differently. We drill the pin holes out to 3/4 of an inch and then dial the bell housing in. When it is right, we lathe a tight fitting bushing and slide it over the engine block pins and then weld the bushing to the bell housing.
David
