CANNOT overstate the importance of dialing in the mainshaft when ANY bellhousing is installed on a powertrain. I have heard of folks taking an out of the box Lakewood, installing it and finding that it is right on.....this is rare.
Yes, it is a pain in the neck, but as others have said, the penalty for not doing so ranges from hard shifting all the way to destroyed transmissions. Actually, once your dial indicator is set up, the hardest part is done. The rest just takes time and patience. Strive for a minimum of +/-.003" or better.
A reminder: If you are using a Lakewood, be sure to use the offset dowels available from Lakewood to align your bell. Some folks drill the bells mounting holes oversize and then weld washers after the bell is centered, but doing any welding on a SFI certified bell may void the certification.
Tip: Make sure that prior to setting up your dial indicator, that you lightly sand the edges of the trans locating hole to remove any paint that could build up and cause an erratic reading.
Bud
